[RFC v3 00/23] powerpc: Memory Protection Keys

[RFC v3 00/23] powerpc: Memory Protection Keys

[Ram Pai]

Memory protection keys enable applications to protect its
address space from inadvertent access or corruption from
itself.

The overall idea:

 A process allocates a   key  and associates it with
 a  address  range  within    its   address   space.
 The process  than  can  dynamically  set read/write 
 permissions on  the   key   without  involving  the 
 kernel. Any  code that  violates   the  permissions
 off the address space; as defined by its associated
 key, will receive a segmentation fault.

This patch series enables the feature on PPC64.
It is enabled on HPTE 64K-page platform.

ISA3.0 section 5.7.13 describes the detailed specifications.


Testing:
	This patch series has passed all the protection key
	tests available in  the selftests directory.
	The tests are updated to work on both x86 and powerpc.

version v3:
	(1) split the patches into smaller consumable
		patches.
	(2) added the ability to disable execute permission
		on a key at creation.
	(3) rename  calc_pte_to_hpte_pkey_bits() to
	    pte_to_hpte_pkey_bits() -- suggested by Anshuman
	(4) some code optimization and clarity in
		do_page_fault()  
	(5) A bug fix while invalidating a hpte slot in 
		__hash_page_4K() -- noticed by Aneesh
	

version v2:
	(1) documentation and selftest added
 	(2) fixed a bug in 4k hpte backed 64k pte where page
	    invalidation was not done correctly, and 
	    initialization of second-part-of-the-pte was not
	    done correctly if the pte was not yet Hashed
	    with a hpte.  Reported by Aneesh.
	(3) Fixed ABI breakage caused in siginfo structure.
		Reported by Anshuman.
	
Outstanding known issue:
    Calls to sys_swapcontext with a made-up context will end 
    up with a crap AMR if done by code who didn't know about
    that register. -- Reported by Ben.

version v1: Initial version

Thanks-to: Dave Hansen, Aneesh, Paul Mackerras,
	   Michael Ellermen


Ram Pai (23):
  powerpc: Free up four 64K PTE bits in 4K backed HPTE pages
  powerpc: introduce set_hidx_slot helper
  powerpc: introduce get_hidx_gslot helper
  powerpc: Free up four 64K PTE bits in 64K backed HPTE pages
  powerpc: capture the PTE format changes in the dump pte report
  powerpc: use helper functions in __hash_page_4K() for 64K PTE
  powerpc: use helper functions in __hash_page_4K() for 4K PTE
  powerpc: use helper functions in flush_hash_page()
  mm: introduce an additional vma bit for powerpc pkey
  mm: provide the ability to disable execute on a key at creation
  x86: key creation with PKEY_DISABLE_EXECUTE is disallowed
  powerpc: Implement sys_pkey_alloc and sys_pkey_free system call
  powerpc: store and restore the pkey state across context switches
  powerpc: Implementation for sys_mprotect_pkey() system call
  powerpc: Program HPTE key protection bits
  powerpc: Macro the mask used for checking DSI exception
  powerpc: Handle exceptions caused by violation of pkey protection
  powerpc: Deliver SEGV signal on pkey violation
  selftest: Move protecton key selftest to arch neutral directory
  selftest: PowerPC specific test updates to memory protection keys
  Documentation: Move protecton key documentation to arch neutral
    directory
  Documentation: PowerPC specific updates to memory protection keys
  procfs: display the protection-key number associated with a vma

 Documentation/filesystems/proc.txt            |    3 +-
 Documentation/vm/protection-keys.txt          |  110 ++
 Documentation/x86/protection-keys.txt         |   85 --
 arch/powerpc/Kconfig                          |   15 +
 arch/powerpc/include/asm/book3s/64/hash-4k.h  |   14 +
 arch/powerpc/include/asm/book3s/64/hash-64k.h |   53 +-
 arch/powerpc/include/asm/book3s/64/hash.h     |   15 +-
 arch/powerpc/include/asm/book3s/64/mmu-hash.h |    5 +
 arch/powerpc/include/asm/book3s/64/mmu.h      |   10 +
 arch/powerpc/include/asm/book3s/64/pgtable.h  |   84 +-
 arch/powerpc/include/asm/mman.h               |   14 +-
 arch/powerpc/include/asm/mmu_context.h        |   12 +
 arch/powerpc/include/asm/paca.h               |    1 +
 arch/powerpc/include/asm/pkeys.h              |  159 +++
 arch/powerpc/include/asm/processor.h          |    5 +
 arch/powerpc/include/asm/reg.h                |    7 +-
 arch/powerpc/include/asm/systbl.h             |    3 +
 arch/powerpc/include/asm/unistd.h             |    6 +-
 arch/powerpc/include/uapi/asm/ptrace.h        |    3 +-
 arch/powerpc/include/uapi/asm/unistd.h        |    3 +
 arch/powerpc/kernel/asm-offsets.c             |    5 +
 arch/powerpc/kernel/exceptions-64s.S          |   18 +-
 arch/powerpc/kernel/process.c                 |   18 +
 arch/powerpc/kernel/signal_32.c               |   14 +
 arch/powerpc/kernel/signal_64.c               |   14 +
 arch/powerpc/kernel/traps.c                   |   49 +
 arch/powerpc/mm/Makefile                      |    1 +
 arch/powerpc/mm/dump_linuxpagetables.c        |    3 +-
 arch/powerpc/mm/fault.c                       |   22 +
 arch/powerpc/mm/hash64_4k.c                   |   14 +-
 arch/powerpc/mm/hash64_64k.c                  |  111 +-
 arch/powerpc/mm/hash_utils_64.c               |   36 +-
 arch/powerpc/mm/hugetlbpage-hash64.c          |   16 +-
 arch/powerpc/mm/mmu_context_book3s64.c        |    5 +
 arch/powerpc/mm/pkeys.c                       |  267 +++++
 arch/x86/kernel/fpu/xstate.c                  |    3 +
 fs/proc/task_mmu.c                            |   18 +-
 include/linux/mm.h                            |   18 +-
 include/uapi/asm-generic/mman-common.h        |    4 +-
 tools/testing/selftests/vm/Makefile           |    1 +
 tools/testing/selftests/vm/pkey-helpers.h     |  365 ++++++
 tools/testing/selftests/vm/protection_keys.c  | 1483 +++++++++++++++++++++++++
 tools/testing/selftests/x86/Makefile          |    2 +-
 tools/testing/selftests/x86/pkey-helpers.h    |  219 ----
 tools/testing/selftests/x86/protection_keys.c | 1395 -----------------------
 45 files changed, 2868 insertions(+), 1840 deletions(-)
 create mode 100644 Documentation/vm/protection-keys.txt
 delete mode 100644 Documentation/x86/protection-keys.txt
 create mode 100644 arch/powerpc/include/asm/pkeys.h
 create mode 100644 arch/powerpc/mm/pkeys.c
 create mode 100644 tools/testing/selftests/vm/pkey-helpers.h
 create mode 100644 tools/testing/selftests/vm/protection_keys.c
 delete mode 100644 tools/testing/selftests/x86/pkey-helpers.h
 delete mode 100644 tools/testing/selftests/x86/protection_keys.c

-- 
1.8.3.1

[RFC v3 01/23] powerpc: Free up four 64K PTE bits in 4K backed HPTE pages

[Ram Pai]

Rearrange 64K PTE bits to  free  up  bits 3, 4, 5  and  6,
in the 4K backed HPTE pages. These bits continue to be used
for 64K backed HPTE pages in this patch,  but will be freed
up in the next patch. The  bit  numbers  are big-endian  as
defined in the ISA3.0

The patch does the following change to the 64K PTE format

H_PAGE_BUSY moves from bit 3 to bit 9
H_PAGE_F_SECOND which occupied bit 4 moves to the second part
	of the pte.
H_PAGE_F_GIX which  occupied bit 5, 6 and 7 also moves to the
	second part of the pte.

the four  bits((H_PAGE_F_SECOND|H_PAGE_F_GIX) that represent a slot
is  initialized  to  0xF  indicating  an invalid  slot.  If  a HPTE
gets cached in a 0xF  slot(i.e  7th  slot  of  secondary),  it   is
released immediately. In  other  words, even  though   0xF   is   a
valid slot we discard  and consider it as an invalid
slot;i.e HPTE(). This  gives  us  an opportunity to not
depend on a bit in the primary PTE in order to determine the
validity of a slot.

When  we  release  a    HPTE   in the 0xF   slot we also   release a
legitimate primary   slot  and    unmap    that  entry. This  is  to
ensure  that we do get a   legimate   non-0xF  slot the next time we
retry for a slot.

Though treating 0xF slot as invalid reduces the number of available
slots  and  may  have an effect  on the performance, the probabilty
of hitting a 0xF is extermely low.

Compared  to the current scheme, the above described scheme reduces
the number of false hash table updates  significantly  and  has the
added  advantage  of  releasing  four  valuable  PTE bits for other
purpose.

This idea was jointly developed by Paul Mackerras, Aneesh, Michael
Ellermen and myself.

4K PTE format remain unchanged currently.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>

Conflicts:
	arch/powerpc/include/asm/book3s/64/hash.h
---
 arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++
 arch/powerpc/include/asm/book3s/64/hash-64k.h | 17 ++++---
 arch/powerpc/include/asm/book3s/64/hash.h     | 12 +++--
 arch/powerpc/mm/hash64_64k.c                  | 70 +++++++++++++++------------
 arch/powerpc/mm/hash_utils_64.c               |  4 +-
 5 files changed, 66 insertions(+), 44 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
index b4b5e6b..9c2c8f1 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
@@ -16,6 +16,13 @@
 #define H_PUD_TABLE_SIZE	(sizeof(pud_t) << H_PUD_INDEX_SIZE)
 #define H_PGD_TABLE_SIZE	(sizeof(pgd_t) << H_PGD_INDEX_SIZE)
 
+#define H_PAGE_F_SECOND        _RPAGE_RSV2     /* HPTE is in 2ndary HPTEG */
+#define H_PAGE_F_GIX           (_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
+#define H_PAGE_F_GIX_SHIFT     56
+
+#define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
+#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
+
 /* PTE flags to conserve for HPTE identification */
 #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | \
 			 H_PAGE_F_SECOND | H_PAGE_F_GIX)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 9732837..3f49941 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -10,20 +10,21 @@
  * 64k aligned address free up few of the lower bits of RPN for us
  * We steal that here. For more deatils look at pte_pfn/pfn_pte()
  */
-#define H_PAGE_COMBO	_RPAGE_RPN0 /* this is a combo 4k page */
-#define H_PAGE_4K_PFN	_RPAGE_RPN1 /* PFN is for a single 4k page */
+#define H_PAGE_COMBO   _RPAGE_RPN0 /* this is a combo 4k page */
+#define H_PAGE_4K_PFN  _RPAGE_RPN1 /* PFN is for a single 4k page */
+#define H_PAGE_F_SECOND	_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
+#define H_PAGE_F_GIX	(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
+#define H_PAGE_F_GIX_SHIFT	56
+
+#define H_PAGE_BUSY	_RPAGE_RPN42     /* software: PTE & hash are busy */
+#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
+
 /*
  * We need to differentiate between explicit huge page and THP huge
  * page, since THP huge page also need to track real subpage details
  */
 #define H_PAGE_THP_HUGE  H_PAGE_4K_PFN
 
-/*
- * Used to track subpage group valid if H_PAGE_COMBO is set
- * This overloads H_PAGE_F_GIX and H_PAGE_F_SECOND
- */
-#define H_PAGE_COMBO_VALID	(H_PAGE_F_GIX | H_PAGE_F_SECOND)
-
 /* PTE flags to conserve for HPTE identification */
 #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_F_SECOND | \
 			 H_PAGE_F_GIX | H_PAGE_HASHPTE | H_PAGE_COMBO)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 4e957b0..ac049de 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -8,11 +8,8 @@
  *
  */
 #define H_PTE_NONE_MASK		_PAGE_HPTEFLAGS
-#define H_PAGE_F_GIX_SHIFT	56
-#define H_PAGE_BUSY		_RPAGE_RSV1 /* software: PTE & hash are busy */
-#define H_PAGE_F_SECOND		_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
-#define H_PAGE_F_GIX		(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
-#define H_PAGE_HASHPTE		_RPAGE_RPN43	/* PTE has associated HPTE */
+
+#define INIT_HIDX (~0x0UL)
 
 #ifdef CONFIG_PPC_64K_PAGES
 #include <asm/book3s/64/hash-64k.h>
@@ -160,6 +157,11 @@ static inline int hash__pte_none(pte_t pte)
 	return (pte_val(pte) & ~H_PTE_NONE_MASK) == 0;
 }
 
+static inline bool hpte_soft_invalid(unsigned long slot)
+{
+	return ((slot & 0xfUL) == 0xfUL);
+}
+
 /* This low level function performs the actual PTE insertion
  * Setting the PTE depends on the MMU type and other factors. It's
  * an horrible mess that I'm not going to try to clean up now but
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index 1a68cb1..a16cd28 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -20,29 +20,7 @@
  */
 bool __rpte_sub_valid(real_pte_t rpte, unsigned long index)
 {
-	unsigned long g_idx;
-	unsigned long ptev = pte_val(rpte.pte);
-
-	g_idx = (ptev & H_PAGE_COMBO_VALID) >> H_PAGE_F_GIX_SHIFT;
-	index = index >> 2;
-	if (g_idx & (0x1 << index))
-		return true;
-	else
-		return false;
-}
-/*
- * index from 0 - 15
- */
-static unsigned long mark_subptegroup_valid(unsigned long ptev, unsigned long index)
-{
-	unsigned long g_idx;
-
-	if (!(ptev & H_PAGE_COMBO))
-		return ptev;
-	index = index >> 2;
-	g_idx = 0x1 << index;
-
-	return ptev | (g_idx << H_PAGE_F_GIX_SHIFT);
+	return !(hpte_soft_invalid(rpte.hidx >> (index << 2)));
 }
 
 int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
@@ -50,12 +28,11 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 		   int ssize, int subpg_prot)
 {
 	real_pte_t rpte;
-	unsigned long *hidxp;
 	unsigned long hpte_group;
 	unsigned int subpg_index;
-	unsigned long rflags, pa, hidx;
+	unsigned long rflags, pa;
 	unsigned long old_pte, new_pte, subpg_pte;
-	unsigned long vpn, hash, slot;
+	unsigned long vpn, hash, slot, gslot;
 	unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift;
 
 	/*
@@ -116,8 +93,8 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 		 * On hash insert failure we use old pte value and we don't
 		 * want slot information there if we have a insert failure.
 		 */
-		old_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
-		new_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
+		old_pte &= ~(H_PAGE_HASHPTE);
+		new_pte &= ~(H_PAGE_HASHPTE);
 		goto htab_insert_hpte;
 	}
 	/*
@@ -148,6 +125,15 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 	}
 
 htab_insert_hpte:
+
+	/*
+	 * initialize all hidx entries to a invalid value,
+	 * the first time the PTE is about to allocate
+	 * a 4K hpte
+	 */
+	if (!(old_pte & H_PAGE_COMBO))
+		rpte.hidx = INIT_HIDX;
+
 	/*
 	 * handle H_PAGE_4K_PFN case
 	 */
@@ -172,15 +158,39 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 	 * Primary is full, try the secondary
 	 */
 	if (unlikely(slot == -1)) {
+		bool soft_invalid;
+
 		hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
 		slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
 						rflags, HPTE_V_SECONDARY,
 						MMU_PAGE_4K, MMU_PAGE_4K,
 						ssize);
-		if (slot == -1) {
-			if (mftb() & 0x1)
+
+		soft_invalid = hpte_soft_invalid(slot);
+		if (unlikely(soft_invalid)) {
+			/* we got a valid slot from a hardware point of view.
+			 * but we cannot use it, because we use this special
+			 * value; as defined by hpte_soft_invalid(),
+			 * to track invalid slots. We cannot use it.
+			 * So invalidate it.
+			 */
+			gslot = slot & _PTEIDX_GROUP_IX;
+			mmu_hash_ops.hpte_invalidate(hpte_group+gslot, vpn,
+				MMU_PAGE_4K, MMU_PAGE_4K,
+				ssize, 0);
+		}
+
+		if (unlikely(slot == -1 || soft_invalid)) {
+			/* for soft invalid slot lets ensure that we
+			 * release a slot from the primary, with the
+			 * hope that we will acquire that slot next
+			 * time we try. This will ensure that we dont
+			 * get the same soft-invalid slot.
+			 */
+			if (soft_invalid || (mftb() & 0x1))
 				hpte_group = ((hash & htab_hash_mask) *
 					      HPTES_PER_GROUP) & ~0x7UL;
+
 			mmu_hash_ops.hpte_remove(hpte_group);
 			/*
 			 * FIXME!! Should be try the group from which we removed ?
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index f2095ce..1b494d0 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -975,8 +975,9 @@ void __init hash__early_init_devtree(void)
 
 void __init hash__early_init_mmu(void)
 {
+#ifndef CONFIG_PPC_64K_PAGES
 	/*
-	 * We have code in __hash_page_64K() and elsewhere, which assumes it can
+	 * We have code in __hash_page_4K() and elsewhere, which assumes it can
 	 * do the following:
 	 *   new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX);
 	 *
@@ -987,6 +988,7 @@ void __init hash__early_init_mmu(void)
 	 * with a BUILD_BUG_ON().
 	 */
 	BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul  << (H_PAGE_F_GIX_SHIFT + 3)));
+#endif /* CONFIG_PPC_64K_PAGES */
 
 	htab_init_page_sizes();
 
-- 
1.8.3.1

[RFC v3 02/23] powerpc: introduce set_hidx_slot helper

[Ram Pai]

Introduce set_hidx_slot() which sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX)
bits at  the  appropriate  location  in  the  PTE  of  4K  PTE.  In the
case of 64K PTE, it sets the bits in the second part of the PTE. Though
the implementation for the former just needs the slot parameter, it does
take some additional parameters to keep the prototype consistent.

This function will come in handy as we  work  towards  re-arranging the
bits in the later patches.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++++++
 arch/powerpc/include/asm/book3s/64/hash-64k.h | 16 ++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
index 9c2c8f1..cef644c 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
@@ -55,6 +55,13 @@ static inline int hash__hugepd_ok(hugepd_t hpd)
 }
 #endif
 
+static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
+			unsigned int subpg_index, unsigned long slot)
+{
+	return (slot << H_PAGE_F_GIX_SHIFT) &
+		(H_PAGE_F_SECOND | H_PAGE_F_GIX);
+}
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 
 static inline char *get_hpte_slot_array(pmd_t *pmdp)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 3f49941..4bac70a 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -75,6 +75,22 @@ static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
 	return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
 }
 
+static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
+		unsigned int subpg_index, unsigned long slot)
+{
+	unsigned long *hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
+
+	rpte.hidx &= ~(0xfUL << (subpg_index << 2));
+	*hidxp = rpte.hidx  | (slot << (subpg_index << 2));
+	/*
+	 * Avoid race with __real_pte()
+	 * hidx must be committed to memory before committing
+	 * the pte.
+	 */
+	smp_wmb();
+	return 0x0UL;
+}
+
 #define __rpte_to_pte(r)	((r).pte)
 extern bool __rpte_sub_valid(real_pte_t rpte, unsigned long index);
 /*
-- 
1.8.3.1

[RFC v3 03/23] powerpc: introduce get_hidx_gslot helper

[Ram Pai]

Introduce get_hidx_gslot() which returns the slot number of the HPTE
in the global hash table.

This function will come in handy as we work towards re-arranging the
PTE bits in the later patches.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/hash.h |  3 +++
 arch/powerpc/mm/hash_utils_64.c           | 14 ++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index ac049de..e7cf03a 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -162,6 +162,9 @@ static inline bool hpte_soft_invalid(unsigned long slot)
 	return ((slot & 0xfUL) == 0xfUL);
 }
 
+unsigned long get_hidx_gslot(unsigned long vpn, unsigned long shift,
+		int ssize, real_pte_t rpte, unsigned int subpg_index);
+
 /* This low level function performs the actual PTE insertion
  * Setting the PTE depends on the MMU type and other factors. It's
  * an horrible mess that I'm not going to try to clean up now but
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 1b494d0..99f97754c 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1591,6 +1591,20 @@ static inline void tm_flush_hash_page(int local)
 }
 #endif
 
+unsigned long get_hidx_gslot(unsigned long vpn, unsigned long shift,
+			int ssize, real_pte_t rpte, unsigned int subpg_index)
+{
+	unsigned long hash, slot, hidx;
+
+	hash = hpt_hash(vpn, shift, ssize);
+	hidx = __rpte_to_hidx(rpte, subpg_index);
+	if (hidx & _PTEIDX_SECONDARY)
+		hash = ~hash;
+	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+	slot += hidx & _PTEIDX_GROUP_IX;
+	return slot;
+}
+
 /* WARNING: This is called from hash_low_64.S, if you change this prototype,
  *          do not forget to update the assembly call site !
  */
-- 
1.8.3.1

[RFC v3 04/23] powerpc: Free up four 64K PTE bits in 64K backed HPTE pages

[Ram Pai]

Rearrange 64K PTE bits to  free  up  bits 3, 4, 5  and  6
in the 64K backed HPTE pages. This along with the earlier
patch will entirely free up the four bits from 64K PTE.
The bit numbers are big-endian as defined in the ISA3.0

This patch does the following change to 64K PTE that is
backed by 64K HPTE.

H_PAGE_F_SECOND which occupied bit 4 moves to the second part
        of the pte.
H_PAGE_F_GIX which  occupied bit 5, 6 and 7 also moves to the
        second part of the pte.

since bit 7 is now freed up, we move H_PAGE_BUSY from bit 9
to bit 7. Trying to minimize gaps so that contiguous bits
can be allocated if needed in the future.

The second part of the PTE will hold
(H_PAGE_F_SECOND|H_PAGE_F_GIX) at bit 60,61,62,63.

The above PTE changes is applicable to hugetlbpages aswell.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/hash-64k.h | 28 +++++++++------------------
 arch/powerpc/mm/hash64_64k.c                  | 17 ++++++++--------
 arch/powerpc/mm/hugetlbpage-hash64.c          | 16 ++++++---------
 3 files changed, 23 insertions(+), 38 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 4bac70a..7b5dbf3 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -12,11 +12,8 @@
  */
 #define H_PAGE_COMBO   _RPAGE_RPN0 /* this is a combo 4k page */
 #define H_PAGE_4K_PFN  _RPAGE_RPN1 /* PFN is for a single 4k page */
-#define H_PAGE_F_SECOND	_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
-#define H_PAGE_F_GIX	(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
-#define H_PAGE_F_GIX_SHIFT	56
 
-#define H_PAGE_BUSY	_RPAGE_RPN42     /* software: PTE & hash are busy */
+#define H_PAGE_BUSY	_RPAGE_RPN44     /* software: PTE & hash are busy */
 #define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
 
 /*
@@ -26,8 +23,7 @@
 #define H_PAGE_THP_HUGE  H_PAGE_4K_PFN
 
 /* PTE flags to conserve for HPTE identification */
-#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_F_SECOND | \
-			 H_PAGE_F_GIX | H_PAGE_HASHPTE | H_PAGE_COMBO)
+#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | H_PAGE_COMBO)
 /*
  * we support 16 fragments per PTE page of 64K size.
  */
@@ -55,24 +51,18 @@ static inline real_pte_t __real_pte(pte_t pte, pte_t *ptep)
 	unsigned long *hidxp;
 
 	rpte.pte = pte;
-	rpte.hidx = 0;
-	if (pte_val(pte) & H_PAGE_COMBO) {
-		/*
-		 * Make sure we order the hidx load against the H_PAGE_COMBO
-		 * check. The store side ordering is done in __hash_page_4K
-		 */
-		smp_rmb();
-		hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
-		rpte.hidx = *hidxp;
-	}
+	/*
+	 * The store side ordering is done in set_hidx_slot()
+	 */
+	smp_rmb();
+	hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
+	rpte.hidx = *hidxp;
 	return rpte;
 }
 
 static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
 {
-	if ((pte_val(rpte.pte) & H_PAGE_COMBO))
-		return (rpte.hidx >> (index<<2)) & 0xf;
-	return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
+	return ((rpte.hidx >> (index<<2)) & 0xfUL);
 }
 
 static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index a16cd28..5cbdaa9 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -231,6 +231,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
 		    unsigned long vsid, pte_t *ptep, unsigned long trap,
 		    unsigned long flags, int ssize)
 {
+	real_pte_t rpte;
 	unsigned long hpte_group;
 	unsigned long rflags, pa;
 	unsigned long old_pte, new_pte;
@@ -267,6 +268,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
 	} while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
 
 	rflags = htab_convert_pte_flags(new_pte);
+	rpte = __real_pte(__pte(old_pte), ptep);
 
 	if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
 	    !cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
@@ -274,16 +276,13 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
 
 	vpn  = hpt_vpn(ea, vsid, ssize);
 	if (unlikely(old_pte & H_PAGE_HASHPTE)) {
+		unsigned long gslot;
+
 		/*
 		 * There MIGHT be an HPTE for this pte
 		 */
-		hash = hpt_hash(vpn, shift, ssize);
-		if (old_pte & H_PAGE_F_SECOND)
-			hash = ~hash;
-		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-		slot += (old_pte & H_PAGE_F_GIX) >> H_PAGE_F_GIX_SHIFT;
-
-		if (mmu_hash_ops.hpte_updatepp(slot, rflags, vpn, MMU_PAGE_64K,
+		gslot = get_hidx_gslot(vpn, shift, ssize, rpte, 0);
+		if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, MMU_PAGE_64K,
 					       MMU_PAGE_64K, ssize,
 					       flags) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
@@ -332,9 +331,9 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
 					   MMU_PAGE_64K, MMU_PAGE_64K, old_pte);
 			return -1;
 		}
+
 		new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE;
-		new_pte |= (slot << H_PAGE_F_GIX_SHIFT) &
-			(H_PAGE_F_SECOND | H_PAGE_F_GIX);
+		new_pte |= set_hidx_slot(ptep, rpte, 0, slot);
 	}
 	*ptep = __pte(new_pte & ~H_PAGE_BUSY);
 	return 0;
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index a84bb44..239ca86 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -22,6 +22,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
 		     pte_t *ptep, unsigned long trap, unsigned long flags,
 		     int ssize, unsigned int shift, unsigned int mmu_psize)
 {
+	real_pte_t rpte;
 	unsigned long vpn;
 	unsigned long old_pte, new_pte;
 	unsigned long rflags, pa, sz;
@@ -61,6 +62,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
 	} while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
 
 	rflags = htab_convert_pte_flags(new_pte);
+	rpte = __real_pte(__pte(old_pte), ptep);
 
 	sz = ((1UL) << shift);
 	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
@@ -71,15 +73,10 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
 	/* Check if pte already has an hpte (case 2) */
 	if (unlikely(old_pte & H_PAGE_HASHPTE)) {
 		/* There MIGHT be an HPTE for this pte */
-		unsigned long hash, slot;
+		unsigned long gslot;
 
-		hash = hpt_hash(vpn, shift, ssize);
-		if (old_pte & H_PAGE_F_SECOND)
-			hash = ~hash;
-		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-		slot += (old_pte & H_PAGE_F_GIX) >> H_PAGE_F_GIX_SHIFT;
-
-		if (mmu_hash_ops.hpte_updatepp(slot, rflags, vpn, mmu_psize,
+		gslot = get_hidx_gslot(vpn, shift, ssize, rpte, 0);
+		if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, mmu_psize,
 					       mmu_psize, ssize, flags) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
 	}
@@ -106,8 +103,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
 			return -1;
 		}
 
-		new_pte |= (slot << H_PAGE_F_GIX_SHIFT) &
-			(H_PAGE_F_SECOND | H_PAGE_F_GIX);
+		new_pte |= set_hidx_slot(ptep, rpte, 0, slot);
 	}
 
 	/*
-- 
1.8.3.1

[RFC v3 05/23] powerpc: capture the PTE format changes in the dump pte report

[Ram Pai]

The H_PAGE_F_SECOND,H_PAGE_F_GIX are not in the 64K main-PTE.
capture these changes in the dump pte report.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/mm/dump_linuxpagetables.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/dump_linuxpagetables.c b/arch/powerpc/mm/dump_linuxpagetables.c
index 44fe483..5627edd 100644
--- a/arch/powerpc/mm/dump_linuxpagetables.c
+++ b/arch/powerpc/mm/dump_linuxpagetables.c
@@ -213,7 +213,7 @@ struct flag_info {
 		.val	= H_PAGE_4K_PFN,
 		.set	= "4K_pfn",
 	}, {
-#endif
+#else /* CONFIG_PPC_64K_PAGES */
 		.mask	= H_PAGE_F_GIX,
 		.val	= H_PAGE_F_GIX,
 		.set	= "f_gix",
@@ -224,6 +224,7 @@ struct flag_info {
 		.val	= H_PAGE_F_SECOND,
 		.set	= "f_second",
 	}, {
+#endif /* CONFIG_PPC_64K_PAGES */
 #endif
 		.mask	= _PAGE_SPECIAL,
 		.val	= _PAGE_SPECIAL,
-- 
1.8.3.1

[RFC v3 06/23] powerpc: use helper functions in __hash_page_4K() for 64K PTE

[Ram Pai]

replace redundant code in __hash_page_4K() with helper
functions get_hidx_gslot() and set_hidx_slot()

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/mm/hash64_64k.c | 24 ++++++------------------
 1 file changed, 6 insertions(+), 18 deletions(-)

diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index 5cbdaa9..cb48a60 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -103,18 +103,12 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 	if (__rpte_sub_valid(rpte, subpg_index)) {
 		int ret;
 
-		hash = hpt_hash(vpn, shift, ssize);
-		hidx = __rpte_to_hidx(rpte, subpg_index);
-		if (hidx & _PTEIDX_SECONDARY)
-			hash = ~hash;
-		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-		slot += hidx & _PTEIDX_GROUP_IX;
-
-		ret = mmu_hash_ops.hpte_updatepp(slot, rflags, vpn,
+		gslot = get_hidx_gslot(vpn, shift, ssize, rpte, subpg_index);
+		ret = mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn,
 						 MMU_PAGE_4K, MMU_PAGE_4K,
 						 ssize, flags);
 		/*
-		 *if we failed because typically the HPTE wasn't really here
+		 * if we failed because typically the HPTE wasn't really here
 		 * we try an insertion.
 		 */
 		if (ret == -1)
@@ -214,15 +208,9 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 	 * Since we have H_PAGE_BUSY set on ptep, we can be sure
 	 * nobody is undating hidx.
 	 */
-	hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
-	rpte.hidx &= ~(0xfUL << (subpg_index << 2));
-	*hidxp = rpte.hidx  | (slot << (subpg_index << 2));
-	new_pte = mark_subptegroup_valid(new_pte, subpg_index);
-	new_pte |=  H_PAGE_HASHPTE;
-	/*
-	 * check __real_pte for details on matching smp_rmb()
-	 */
-	smp_wmb();
+	new_pte |= H_PAGE_HASHPTE;
+	new_pte |= set_hidx_slot(ptep, rpte, subpg_index, slot);
+
 	*ptep = __pte(new_pte & ~H_PAGE_BUSY);
 	return 0;
 }
-- 
1.8.3.1

[RFC v3 07/23] powerpc: use helper functions in __hash_page_4K() for 4K PTE

[Ram Pai]

replace redundant code with helper functions
get_hidx_gslot() and set_hidx_slot()

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/mm/hash64_4k.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index 6fa450c..c673829 100644
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -20,6 +20,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 		   pte_t *ptep, unsigned long trap, unsigned long flags,
 		   int ssize, int subpg_prot)
 {
+	real_pte_t rpte;
 	unsigned long hpte_group;
 	unsigned long rflags, pa;
 	unsigned long old_pte, new_pte;
@@ -54,6 +55,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 	 * need to add in 0x1 if it's a read-only user page
 	 */
 	rflags = htab_convert_pte_flags(new_pte);
+	rpte = __real_pte(__pte(old_pte), ptep);
 
 	if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
 	    !cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
@@ -64,13 +66,10 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 		/*
 		 * There MIGHT be an HPTE for this pte
 		 */
-		hash = hpt_hash(vpn, shift, ssize);
-		if (old_pte & H_PAGE_F_SECOND)
-			hash = ~hash;
-		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-		slot += (old_pte & H_PAGE_F_GIX) >> H_PAGE_F_GIX_SHIFT;
+		unsigned long gslot = get_hidx_gslot(vpn, shift,
+						ssize, rpte, 0);
 
-		if (mmu_hash_ops.hpte_updatepp(slot, rflags, vpn, MMU_PAGE_4K,
+		if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, MMU_PAGE_4K,
 					       MMU_PAGE_4K, ssize, flags) == -1)
 			old_pte &= ~_PAGE_HPTEFLAGS;
 	}
@@ -118,8 +117,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 			return -1;
 		}
 		new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE;
-		new_pte |= (slot << H_PAGE_F_GIX_SHIFT) &
-			(H_PAGE_F_SECOND | H_PAGE_F_GIX);
+		new_pte |= set_hidx_slot(ptep, rpte, 0, slot);
 	}
 	*ptep = __pte(new_pte & ~H_PAGE_BUSY);
 	return 0;
-- 
1.8.3.1

[RFC v3 08/23] powerpc: use helper functions in flush_hash_page()

[Ram Pai]

replace redundant code in flush_hash_page() with helper functions
get_hidx_gslot() and set_hidx_slot()

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/mm/hash_utils_64.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 99f97754c..b3bc5d6 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1611,23 +1611,18 @@ unsigned long get_hidx_gslot(unsigned long vpn, unsigned long shift,
 void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize,
 		     unsigned long flags)
 {
-	unsigned long hash, index, shift, hidx, slot;
+	unsigned long index, shift, gslot;
 	int local = flags & HPTE_LOCAL_UPDATE;
 
 	DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn);
 	pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
-		hash = hpt_hash(vpn, shift, ssize);
-		hidx = __rpte_to_hidx(pte, index);
-		if (hidx & _PTEIDX_SECONDARY)
-			hash = ~hash;
-		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-		slot += hidx & _PTEIDX_GROUP_IX;
-		DBG_LOW(" sub %ld: hash=%lx, hidx=%lx\n", index, slot, hidx);
+		gslot = get_hidx_gslot(vpn, shift, ssize, pte, index);
+		DBG_LOW(" sub %ld: gslot=%lx\n", index, gslot);
 		/*
 		 * We use same base page size and actual psize, because we don't
 		 * use these functions for hugepage
 		 */
-		mmu_hash_ops.hpte_invalidate(slot, vpn, psize, psize,
+		mmu_hash_ops.hpte_invalidate(gslot, vpn, psize, psize,
 					     ssize, local);
 	} pte_iterate_hashed_end();
 
-- 
1.8.3.1

[RFC v3 09/23] mm: introduce an additional vma bit for powerpc pkey

[Ram Pai]

Currently there are only 4bits in the vma flags to support 16 keys
on x86.  powerpc supports 32 keys, which needs 5bits. This patch
introduces an addition bit in the vma flags.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 fs/proc/task_mmu.c |  6 +++++-
 include/linux/mm.h | 18 +++++++++++++-----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f0c8b33..2ddc298 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -666,12 +666,16 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_MERGEABLE)]	= "mg",
 		[ilog2(VM_UFFD_MISSING)]= "um",
 		[ilog2(VM_UFFD_WP)]	= "uw",
-#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+#ifdef CONFIG_ARCH_HAS_PKEYS
 		/* These come out via ProtectionKey: */
 		[ilog2(VM_PKEY_BIT0)]	= "",
 		[ilog2(VM_PKEY_BIT1)]	= "",
 		[ilog2(VM_PKEY_BIT2)]	= "",
 		[ilog2(VM_PKEY_BIT3)]	= "",
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+		/* Additional bit in ProtectionKey: */
+		[ilog2(VM_PKEY_BIT4)]	= "",
 #endif
 	};
 	size_t i;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7cb17c6..3d35bcc 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -208,21 +208,29 @@ extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
 #define VM_HIGH_ARCH_BIT_1	33	/* bit only usable on 64-bit architectures */
 #define VM_HIGH_ARCH_BIT_2	34	/* bit only usable on 64-bit architectures */
 #define VM_HIGH_ARCH_BIT_3	35	/* bit only usable on 64-bit architectures */
+#define VM_HIGH_ARCH_BIT_4	36	/* bit only usable on 64-bit arch */
 #define VM_HIGH_ARCH_0	BIT(VM_HIGH_ARCH_BIT_0)
 #define VM_HIGH_ARCH_1	BIT(VM_HIGH_ARCH_BIT_1)
 #define VM_HIGH_ARCH_2	BIT(VM_HIGH_ARCH_BIT_2)
 #define VM_HIGH_ARCH_3	BIT(VM_HIGH_ARCH_BIT_3)
+#define VM_HIGH_ARCH_4	BIT(VM_HIGH_ARCH_BIT_4)
 #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
 
-#if defined(CONFIG_X86)
-# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
-#if defined (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS)
+#ifdef CONFIG_ARCH_HAS_PKEYS
 # define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
-# define VM_PKEY_BIT0	VM_HIGH_ARCH_0	/* A protection key is a 4-bit value */
+# define VM_PKEY_BIT0	VM_HIGH_ARCH_0
 # define VM_PKEY_BIT1	VM_HIGH_ARCH_1
 # define VM_PKEY_BIT2	VM_HIGH_ARCH_2
 # define VM_PKEY_BIT3	VM_HIGH_ARCH_3
-#endif
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+
+#if defined(CONFIG_PPC64_MEMORY_PROTECTION_KEYS)
+# define VM_PKEY_BIT4	VM_HIGH_ARCH_4 /* additional key bit used on ppc64 */
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+
+#if defined(CONFIG_X86)
+# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
 #elif defined(CONFIG_PPC)
 # define VM_SAO		VM_ARCH_1	/* Strong Access Ordering (powerpc) */
 #elif defined(CONFIG_PARISC)
-- 
1.8.3.1

[RFC v3 10/23] mm: provide the ability to disable execute on a key at creation

[Ram Pai]

Currently sys_pkey_create() provides the ability to disable read
and write permission on the key, at  creation. powerpc  has  the
hardware support to disable execute on a pkey as well.This patch
enhances the interface to let disable execute  at  key  creation
time. x86 does  not  allow  this.  Hence the next patch will add
ability  in  x86  to  return  error  is  PKEY_DISABLE_EXECUTE is
specified.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 include/uapi/asm-generic/mman-common.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index 8c27db0..bf4fa07 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -74,7 +74,9 @@
 
 #define PKEY_DISABLE_ACCESS	0x1
 #define PKEY_DISABLE_WRITE	0x2
+#define PKEY_DISABLE_EXECUTE	0x4
 #define PKEY_ACCESS_MASK	(PKEY_DISABLE_ACCESS |\
-				 PKEY_DISABLE_WRITE)
+				 PKEY_DISABLE_WRITE  |\
+				 PKEY_DISABLE_EXECUTE)
 
 #endif /* __ASM_GENERIC_MMAN_COMMON_H */
-- 
1.8.3.1

[RFC v3 11/23] x86: key creation with PKEY_DISABLE_EXECUTE is disallowed

[Ram Pai]

x86 does not support disabling execute permissions on a pkey.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/x86/kernel/fpu/xstate.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c24ac1e..d582631 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -900,6 +900,9 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 	if (!boot_cpu_has(X86_FEATURE_OSPKE))
 		return -EINVAL;
 
+	if (init_val & PKEY_DISABLE_EXECUTE)
+		return -EINVAL;
+
 	/* Set the bits we need in PKRU:  */
 	if (init_val & PKEY_DISABLE_ACCESS)
 		new_pkru_bits |= PKRU_AD_BIT;
-- 
1.8.3.1

[RFC v3 12/23] powerpc: Implement sys_pkey_alloc and sys_pkey_free system call

[Ram Pai]

Sys_pkey_alloc() allocates and returns available pkey
Sys_pkey_free()  frees up the pkey.

Total 32 keys are supported on powerpc. However pkey 0,1 and 31
are reserved. So effectively we have 29 pkeys.

Each key  can  be  initialized  to disable read, write and execute
permissions. On powerpc a key can be initialize to disable execute.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/Kconfig                         |  15 ++++
 arch/powerpc/include/asm/book3s/64/mmu.h     |  10 +++
 arch/powerpc/include/asm/book3s/64/pgtable.h |  62 ++++++++++++++
 arch/powerpc/include/asm/pkeys.h             | 124 +++++++++++++++++++++++++++
 arch/powerpc/include/asm/systbl.h            |   2 +
 arch/powerpc/include/asm/unistd.h            |   4 +-
 arch/powerpc/include/uapi/asm/unistd.h       |   2 +
 arch/powerpc/mm/Makefile                     |   1 +
 arch/powerpc/mm/mmu_context_book3s64.c       |   5 ++
 arch/powerpc/mm/pkeys.c                      |  88 +++++++++++++++++++
 10 files changed, 310 insertions(+), 3 deletions(-)
 create mode 100644 arch/powerpc/include/asm/pkeys.h
 create mode 100644 arch/powerpc/mm/pkeys.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index f7c8f99..b6960617 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -871,6 +871,21 @@ config SECCOMP
 
 	  If unsure, say Y. Only embedded should say N here.
 
+config PPC64_MEMORY_PROTECTION_KEYS
+	prompt "PowerPC Memory Protection Keys"
+	def_bool y
+	# Note: only available in 64-bit mode
+	depends on PPC64 && PPC_64K_PAGES
+	select ARCH_USES_HIGH_VMA_FLAGS
+	select ARCH_HAS_PKEYS
+	---help---
+	  Memory Protection Keys provides a mechanism for enforcing
+	  page-based protections, but without requiring modification of the
+	  page tables when an application changes protection domains.
+
+	  For details, see Documentation/powerpc/protection-keys.txt
+
+	  If unsure, say y.
 endmenu
 
 config ISA_DMA_API
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index 77529a3..0c0a2a8 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -108,6 +108,16 @@ struct patb_entry {
 #ifdef CONFIG_SPAPR_TCE_IOMMU
 	struct list_head iommu_group_mem_list;
 #endif
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	/*
+	 * Each bit represents one protection key.
+	 * bit set   -> key allocated
+	 * bit unset -> key available for allocation
+	 */
+	u32 pkey_allocation_map;
+	s16 execute_only_pkey; /* key holding execute-only protection */
+#endif
 } mm_context_t;
 
 /*
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 85bc987..87e9a89 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -428,6 +428,68 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
 		pte_update(mm, addr, ptep, 0, _PAGE_PRIVILEGED, 1);
 }
 
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+
+#include <asm/reg.h>
+static inline u64 read_amr(void)
+{
+	return mfspr(SPRN_AMR);
+}
+static inline void write_amr(u64 value)
+{
+	mtspr(SPRN_AMR, value);
+}
+static inline u64 read_iamr(void)
+{
+	return mfspr(SPRN_IAMR);
+}
+static inline void write_iamr(u64 value)
+{
+	mtspr(SPRN_IAMR, value);
+}
+static inline u64 read_uamor(void)
+{
+	return mfspr(SPRN_UAMOR);
+}
+static inline void write_uamor(u64 value)
+{
+	mtspr(SPRN_UAMOR, value);
+}
+
+#else /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+static inline u64 read_amr(void)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+	return -1;
+}
+static inline void write_amr(u64 value)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+static inline u64 read_uamor(void)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+	return -1;
+}
+static inline void write_uamor(u64 value)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+static inline u64 read_iamr(void)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+	return -1;
+}
+static inline void write_iamr(u64 value)
+{
+	WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+
 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 				       unsigned long addr, pte_t *ptep)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
new file mode 100644
index 0000000..7bc8746
--- /dev/null
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -0,0 +1,124 @@
+#ifndef _ASM_PPC64_PKEYS_H
+#define _ASM_PPC64_PKEYS_H
+
+
+#define arch_max_pkey()  32
+
+#define AMR_AD_BIT 0x1UL
+#define AMR_WD_BIT 0x2UL
+#define IAMR_EX_BIT 0x1UL
+#define AMR_BITS_PER_PKEY 2
+#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | \
+			VM_PKEY_BIT1 | \
+			VM_PKEY_BIT2 | \
+			VM_PKEY_BIT3 | \
+			VM_PKEY_BIT4)
+
+/*
+ * Bits are in BE format.
+ * NOTE: key 31, 1, 0 are not used.
+ * key 0 is used by default. It give read/write/execute permission.
+ * key 31 is reserved by the hypervisor.
+ * key 1 is recommended to be not used.
+ * PowerISA(3.0) page 1015, programming note.
+ */
+#define PKEY_INITIAL_ALLOCAION  0xc0000001
+
+#define pkeybit_mask(pkey) (0x1 << (arch_max_pkey() - pkey - 1))
+
+#define mm_pkey_allocation_map(mm)	(mm->context.pkey_allocation_map)
+
+#define mm_set_pkey_allocated(mm, pkey) {	\
+	mm_pkey_allocation_map(mm) |= pkeybit_mask(pkey); \
+}
+
+#define mm_set_pkey_free(mm, pkey) {	\
+	mm_pkey_allocation_map(mm) &= ~pkeybit_mask(pkey);	\
+}
+
+#define mm_set_pkey_is_allocated(mm, pkey)	\
+	(mm_pkey_allocation_map(mm) & pkeybit_mask(pkey))
+
+#define mm_set_pkey_is_reserved(mm, pkey) (PKEY_INITIAL_ALLOCAION & \
+					pkeybit_mask(pkey))
+
+static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
+{
+	/* a reserved key is never considered as 'explicitly allocated' */
+	return (!mm_set_pkey_is_reserved(mm, pkey) &&
+		mm_set_pkey_is_allocated(mm, pkey));
+}
+
+/*
+ * Returns a positive, 5-bit key on success, or -1 on failure.
+ */
+static inline int mm_pkey_alloc(struct mm_struct *mm)
+{
+	/*
+	 * Note: this is the one and only place we make sure
+	 * that the pkey is valid as far as the hardware is
+	 * concerned.  The rest of the kernel trusts that
+	 * only good, valid pkeys come out of here.
+	 */
+	u32 all_pkeys_mask = (u32)(~(0x0));
+	int ret;
+
+	/*
+	 * Are we out of pkeys?  We must handle this specially
+	 * because ffz() behavior is undefined if there are no
+	 * zeros.
+	 */
+	if (mm_pkey_allocation_map(mm) == all_pkeys_mask)
+		return -1;
+
+	ret = arch_max_pkey() -
+		ffz((u32)mm_pkey_allocation_map(mm))
+		- 1;
+	mm_set_pkey_allocated(mm, ret);
+	return ret;
+}
+
+static inline int mm_pkey_free(struct mm_struct *mm, int pkey)
+{
+	if (!mm_pkey_is_allocated(mm, pkey))
+		return -EINVAL;
+
+	mm_set_pkey_free(mm, pkey);
+
+	return 0;
+}
+
+/*
+ * Try to dedicate one of the protection keys to be used as an
+ * execute-only protection key.
+ */
+extern int __execute_only_pkey(struct mm_struct *mm);
+static inline int execute_only_pkey(struct mm_struct *mm)
+{
+	return __execute_only_pkey(mm);
+}
+
+extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
+		int prot, int pkey);
+static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
+		int prot, int pkey)
+{
+	return __arch_override_mprotect_pkey(vma, prot, pkey);
+}
+
+extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+		unsigned long init_val);
+static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+		unsigned long init_val)
+{
+	return __arch_set_user_pkey_access(tsk, pkey, init_val);
+}
+
+static inline pkey_mm_init(struct mm_struct *mm)
+{
+	mm_pkey_allocation_map(mm) = PKEY_INITIAL_ALLOCAION;
+	/* -1 means unallocated or invalid */
+	mm->context.execute_only_pkey = -1;
+}
+
+#endif /*_ASM_PPC64_PKEYS_H */
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 1c94708..22dd776 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -388,3 +388,5 @@
 COMPAT_SYS_SPU(pwritev2)
 SYSCALL(kexec_file_load)
 SYSCALL(statx)
+SYSCALL(pkey_alloc)
+SYSCALL(pkey_free)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index 9ba11db..e0273bc 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -12,13 +12,11 @@
 #include <uapi/asm/unistd.h>
 
 
-#define NR_syscalls		384
+#define NR_syscalls		386
 
 #define __NR__exit __NR_exit
 
 #define __IGNORE_pkey_mprotect
-#define __IGNORE_pkey_alloc
-#define __IGNORE_pkey_free
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index b85f142..7993a07 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -394,5 +394,7 @@
 #define __NR_pwritev2		381
 #define __NR_kexec_file_load	382
 #define __NR_statx		383
+#define __NR_pkey_alloc		384
+#define __NR_pkey_free		385
 
 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 7414034..8cc2ff1 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -45,3 +45,4 @@ obj-$(CONFIG_PPC_COPRO_BASE)	+= copro_fault.o
 obj-$(CONFIG_SPAPR_TCE_IOMMU)	+= mmu_context_iommu.o
 obj-$(CONFIG_PPC_PTDUMP)	+= dump_linuxpagetables.o
 obj-$(CONFIG_PPC_HTDUMP)	+= dump_hashpagetable.o
+obj-$(CONFIG_PPC64_MEMORY_PROTECTION_KEYS)	+= pkeys.o
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
index c6dca2a..2da9931 100644
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -16,6 +16,7 @@
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/mm.h>
+#include <linux/pkeys.h>
 #include <linux/spinlock.h>
 #include <linux/idr.h>
 #include <linux/export.h>
@@ -120,6 +121,10 @@ static int hash__init_new_context(struct mm_struct *mm)
 
 	subpage_prot_init_new_context(mm);
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	pkey_mm_init(mm);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	return index;
 }
 
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
new file mode 100644
index 0000000..b97366e
--- /dev/null
+++ b/arch/powerpc/mm/pkeys.c
@@ -0,0 +1,88 @@
+/*
+ * PowerPC Memory Protection Keys management
+ * Copyright (c) 2015, Intel Corporation.
+ * Copyright (c) 2017, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#include <linux/pkeys.h>                /* PKEY_*                       */
+#include <uapi/asm-generic/mman-common.h>
+
+
+/*
+ * set the access right in AMR IAMR and UAMOR register
+ * for @pkey to that specified in @init_val.
+ */
+int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+		unsigned long init_val)
+{
+	u64 old_amr, old_uamor, old_iamr;
+	int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+	u64 new_amr_bits = 0x0ul;
+	u64 new_iamr_bits = 0x0ul;
+	u64 new_uamor_bits = 0x3ul;
+
+	/* Set the bits we need in AMR:  */
+	if (init_val & PKEY_DISABLE_ACCESS)
+		new_amr_bits |= AMR_AD_BIT;
+	if (init_val & PKEY_DISABLE_WRITE)
+		new_amr_bits |= AMR_WD_BIT;
+
+	/*
+	 * By default execute is disabled.
+	 * To enable execute, PKEY_ENABLE_EXECUTE
+	 * needs to be specified.
+	 */
+	if ((init_val & PKEY_DISABLE_EXECUTE))
+		new_iamr_bits |= IAMR_EX_BIT;
+
+	/* Shift the bits in to the correct place in AMR for pkey: */
+	new_amr_bits	<<= pkey_shift;
+	new_iamr_bits	<<= pkey_shift;
+	new_uamor_bits	<<= pkey_shift;
+
+	/* Get old AMR and mask off any old bits in place: */
+	old_amr	= read_amr();
+	old_amr	&= ~((u64)(AMR_AD_BIT|AMR_WD_BIT) << pkey_shift);
+
+	old_iamr = read_iamr();
+	old_iamr &= ~(0x3ul << pkey_shift);
+
+	old_uamor = read_uamor();
+	old_uamor &= ~(0x3ul << pkey_shift);
+
+	/* Write old part along with new part: */
+	write_amr(old_amr | new_amr_bits);
+	write_iamr(old_iamr | new_iamr_bits);
+	write_uamor(old_uamor | new_uamor_bits);
+
+	return 0;
+}
+
+int __execute_only_pkey(struct mm_struct *mm)
+{
+	return -1;
+}
+
+/*
+ * This should only be called for *plain* mprotect calls.
+ */
+int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
+		int pkey)
+{
+	/*
+	 * Is this an mprotect_pkey() call?  If so, never
+	 * override the value that came from the user.
+	 */
+	if (pkey != -1)
+		return pkey;
+
+	return 0;
+}
-- 
1.8.3.1

[RFC v3 13/23] powerpc: store and restore the pkey state across context switches

[Ram Pai]

Store and restore the AMR, IAMR and UMOR register state of the task
before scheduling out and after scheduling in, respectively.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/processor.h |  5 +++++
 arch/powerpc/kernel/process.c        | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index a2123f2..1f714df 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -310,6 +310,11 @@ struct thread_struct {
 	struct thread_vr_state ckvr_state; /* Checkpointed VR state */
 	unsigned long	ckvrsave; /* Checkpointed VRSAVE */
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	unsigned long	amr;
+	unsigned long	iamr;
+	unsigned long	uamor;
+#endif
 #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
 	void*		kvm_shadow_vcpu; /* KVM internal data */
 #endif /* CONFIG_KVM_BOOK3S_32_HANDLER */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index baae104..37d001a 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1096,6 +1096,11 @@ static inline void save_sprs(struct thread_struct *t)
 		t->tar = mfspr(SPRN_TAR);
 	}
 #endif
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	t->amr = mfspr(SPRN_AMR);
+	t->iamr = mfspr(SPRN_IAMR);
+	t->uamor = mfspr(SPRN_UAMOR);
+#endif
 }
 
 static inline void restore_sprs(struct thread_struct *old_thread,
@@ -1131,6 +1136,14 @@ static inline void restore_sprs(struct thread_struct *old_thread,
 			mtspr(SPRN_TAR, new_thread->tar);
 	}
 #endif
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	if (old_thread->amr != new_thread->amr)
+		mtspr(SPRN_AMR, new_thread->amr);
+	if (old_thread->iamr != new_thread->iamr)
+		mtspr(SPRN_IAMR, new_thread->iamr);
+	if (old_thread->uamor != new_thread->uamor)
+		mtspr(SPRN_UAMOR, new_thread->uamor);
+#endif
 }
 
 struct task_struct *__switch_to(struct task_struct *prev,
@@ -1686,6 +1699,11 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
 	current->thread.tm_texasr = 0;
 	current->thread.tm_tfiar = 0;
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	current->thread.amr   = 0x0ul;
+	current->thread.iamr  = 0x0ul;
+	current->thread.uamor = 0x0ul;
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
 }
 EXPORT_SYMBOL(start_thread);
 
-- 
1.8.3.1

[RFC v3 14/23] powerpc: Implementation for sys_mprotect_pkey() system call

[Ram Pai]

This system call, associates the pkey with PTE of all
pages covering the given address range.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/pgtable.h | 22 ++++++-
 arch/powerpc/include/asm/mman.h              | 14 ++++-
 arch/powerpc/include/asm/pkeys.h             | 21 ++++++-
 arch/powerpc/include/asm/systbl.h            |  1 +
 arch/powerpc/include/asm/unistd.h            |  4 +-
 arch/powerpc/include/uapi/asm/unistd.h       |  1 +
 arch/powerpc/mm/pkeys.c                      | 93 +++++++++++++++++++++++++++-
 7 files changed, 148 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 87e9a89..bc845cd 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -37,6 +37,7 @@
 #define _RPAGE_RSV2		0x0800000000000000UL
 #define _RPAGE_RSV3		0x0400000000000000UL
 #define _RPAGE_RSV4		0x0200000000000000UL
+#define _RPAGE_RSV5		0x00040UL
 
 #define _PAGE_PTE		0x4000000000000000UL	/* distinguishes PTEs from pointers */
 #define _PAGE_PRESENT		0x8000000000000000UL	/* pte contains a translation */
@@ -56,6 +57,20 @@
 /* Max physical address bit as per radix table */
 #define _RPAGE_PA_MAX		57
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+#define H_PAGE_PKEY_BIT0	_RPAGE_RSV1
+#define H_PAGE_PKEY_BIT1	_RPAGE_RSV2
+#define H_PAGE_PKEY_BIT2	_RPAGE_RSV3
+#define H_PAGE_PKEY_BIT3	_RPAGE_RSV4
+#define H_PAGE_PKEY_BIT4	_RPAGE_RSV5
+#else /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+#define H_PAGE_PKEY_BIT0	0
+#define H_PAGE_PKEY_BIT1	0
+#define H_PAGE_PKEY_BIT2	0
+#define H_PAGE_PKEY_BIT3	0
+#define H_PAGE_PKEY_BIT4	0
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 /*
  * Max physical address bit we will use for now.
  *
@@ -122,7 +137,12 @@
 #define PAGE_PROT_BITS  (_PAGE_SAO | _PAGE_NON_IDEMPOTENT | _PAGE_TOLERANT | \
 			 H_PAGE_4K_PFN | _PAGE_PRIVILEGED | _PAGE_ACCESSED | \
 			 _PAGE_READ | _PAGE_WRITE |  _PAGE_DIRTY | _PAGE_EXEC | \
-			 _PAGE_SOFT_DIRTY)
+			 _PAGE_SOFT_DIRTY | \
+			 H_PAGE_PKEY_BIT0 | \
+			 H_PAGE_PKEY_BIT1 | \
+			 H_PAGE_PKEY_BIT2 | \
+			 H_PAGE_PKEY_BIT3 | \
+			 H_PAGE_PKEY_BIT4)
 /*
  * We define 2 sets of base prot bits, one for basic pages (ie,
  * cacheable kernel and user pages) and one for non cacheable
diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
index 30922f6..624f6a2 100644
--- a/arch/powerpc/include/asm/mman.h
+++ b/arch/powerpc/include/asm/mman.h
@@ -13,6 +13,7 @@
 
 #include <asm/cputable.h>
 #include <linux/mm.h>
+#include <linux/pkeys.h>
 #include <asm/cpu_has_feature.h>
 
 /*
@@ -22,13 +23,24 @@
 static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
 		unsigned long pkey)
 {
-	return (prot & PROT_SAO) ? VM_SAO : 0;
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	return (((prot & PROT_SAO) ? VM_SAO : 0) |
+			pkey_to_vmflag_bits(pkey));
+#else
+	return ((prot & PROT_SAO) ? VM_SAO : 0);
+#endif
 }
 #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
 
 static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags)
 {
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	return (vm_flags & VM_SAO) ?
+		__pgprot(_PAGE_SAO | vmflag_to_page_pkey_bits(vm_flags)) :
+		__pgprot(0 | vmflag_to_page_pkey_bits(vm_flags));
+#else
 	return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) : __pgprot(0);
+#endif
 }
 #define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags)
 
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 7bc8746..0f3dca8 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -14,6 +14,19 @@
 			VM_PKEY_BIT3 | \
 			VM_PKEY_BIT4)
 
+#define pkey_to_vmflag_bits(key) (((key & 0x1UL) ? VM_PKEY_BIT0 : 0x0UL) | \
+			((key & 0x2UL) ? VM_PKEY_BIT1 : 0x0UL) |	\
+			((key & 0x4UL) ? VM_PKEY_BIT2 : 0x0UL) |	\
+			((key & 0x8UL) ? VM_PKEY_BIT3 : 0x0UL) |	\
+			((key & 0x10UL) ? VM_PKEY_BIT4 : 0x0UL))
+
+#define vmflag_to_page_pkey_bits(vm_flags)  \
+		(((vm_flags & VM_PKEY_BIT0) ? H_PAGE_PKEY_BIT4 : 0x0UL)|     \
+		((vm_flags & VM_PKEY_BIT1) ? H_PAGE_PKEY_BIT3 : 0x0UL) |     \
+		((vm_flags & VM_PKEY_BIT2) ? H_PAGE_PKEY_BIT2 : 0x0UL) |     \
+		((vm_flags & VM_PKEY_BIT3) ? H_PAGE_PKEY_BIT1 : 0x0UL) |     \
+		((vm_flags & VM_PKEY_BIT4) ? H_PAGE_PKEY_BIT0 : 0x0UL))
+
 /*
  * Bits are in BE format.
  * NOTE: key 31, 1, 0 are not used.
@@ -42,6 +55,12 @@
 #define mm_set_pkey_is_reserved(mm, pkey) (PKEY_INITIAL_ALLOCAION & \
 					pkeybit_mask(pkey))
 
+
+static inline int vma_pkey(struct vm_area_struct *vma)
+{
+	return (vma->vm_flags & ARCH_VM_PKEY_FLAGS) >> VM_PKEY_SHIFT;
+}
+
 static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
 {
 	/* a reserved key is never considered as 'explicitly allocated' */
@@ -114,7 +133,7 @@ static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 	return __arch_set_user_pkey_access(tsk, pkey, init_val);
 }
 
-static inline pkey_mm_init(struct mm_struct *mm)
+static inline void pkey_mm_init(struct mm_struct *mm)
 {
 	mm_pkey_allocation_map(mm) = PKEY_INITIAL_ALLOCAION;
 	/* -1 means unallocated or invalid */
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 22dd776..b33b551 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -390,3 +390,4 @@
 SYSCALL(statx)
 SYSCALL(pkey_alloc)
 SYSCALL(pkey_free)
+SYSCALL(pkey_mprotect)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index e0273bc..daf1ba9 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -12,12 +12,10 @@
 #include <uapi/asm/unistd.h>
 
 
-#define NR_syscalls		386
+#define NR_syscalls		387
 
 #define __NR__exit __NR_exit
 
-#define __IGNORE_pkey_mprotect
-
 #ifndef __ASSEMBLY__
 
 #include <linux/types.h>
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index 7993a07..71ae45e 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -396,5 +396,6 @@
 #define __NR_statx		383
 #define __NR_pkey_alloc		384
 #define __NR_pkey_free		385
+#define __NR_pkey_mprotect	386
 
 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index b97366e..11a32b3 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -15,6 +15,17 @@
 #include <linux/pkeys.h>                /* PKEY_*                       */
 #include <uapi/asm-generic/mman-common.h>
 
+#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
+
+static inline bool pkey_allows_readwrite(int pkey)
+{
+	int pkey_shift = pkeyshift(pkey);
+
+	if (!(read_uamor() & (0x3UL << pkey_shift)))
+		return true;
+
+	return !(read_amr() & ((AMR_AD_BIT|AMR_WD_BIT) << pkey_shift));
+}
 
 /*
  * set the access right in AMR IAMR and UAMOR register
@@ -68,7 +79,60 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 
 int __execute_only_pkey(struct mm_struct *mm)
 {
-	return -1;
+	bool need_to_set_mm_pkey = false;
+	int execute_only_pkey = mm->context.execute_only_pkey;
+	int ret;
+
+	/* Do we need to assign a pkey for mm's execute-only maps? */
+	if (execute_only_pkey == -1) {
+		/* Go allocate one to use, which might fail */
+		execute_only_pkey = mm_pkey_alloc(mm);
+		if (execute_only_pkey < 0)
+			return -1;
+		need_to_set_mm_pkey = true;
+	}
+
+	/*
+	 * We do not want to go through the relatively costly
+	 * dance to set AMR if we do not need to.  Check it
+	 * first and assume that if the execute-only pkey is
+	 * readwrite-disabled than we do not have to set it
+	 * ourselves.
+	 */
+	if (!need_to_set_mm_pkey &&
+	    !pkey_allows_readwrite(execute_only_pkey))
+		return execute_only_pkey;
+
+	/*
+	 * Set up AMR so that it denies access for everything
+	 * other than execution.
+	 */
+	ret = __arch_set_user_pkey_access(current, execute_only_pkey,
+			(PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+	/*
+	 * If the AMR-set operation failed somehow, just return
+	 * 0 and effectively disable execute-only support.
+	 */
+	if (ret) {
+		mm_set_pkey_free(mm, execute_only_pkey);
+		return -1;
+	}
+
+	/* We got one, store it and use it from here on out */
+	if (need_to_set_mm_pkey)
+		mm->context.execute_only_pkey = execute_only_pkey;
+	return execute_only_pkey;
+}
+
+static inline bool vma_is_pkey_exec_only(struct vm_area_struct *vma)
+{
+	/* Do this check first since the vm_flags should be hot */
+	if ((vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)) != VM_EXEC)
+		return false;
+	if (vma_pkey(vma) != vma->vm_mm->context.execute_only_pkey)
+		return false;
+
+	return true;
 }
 
 /*
@@ -84,5 +148,30 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
 	if (pkey != -1)
 		return pkey;
 
-	return 0;
+	/*
+	 * Look for a protection-key-drive execute-only mapping
+	 * which is now being given permissions that are not
+	 * execute-only.  Move it back to the default pkey.
+	 */
+	if (vma_is_pkey_exec_only(vma) &&
+	    (prot & (PROT_READ|PROT_WRITE))) {
+		return 0;
+	}
+	/*
+	 * The mapping is execute-only.  Go try to get the
+	 * execute-only protection key.  If we fail to do that,
+	 * fall through as if we do not have execute-only
+	 * support.
+	 */
+	if (prot == PROT_EXEC) {
+		pkey = execute_only_pkey(vma->vm_mm);
+		if (pkey > 0)
+			return pkey;
+	}
+	/*
+	 * This is a vanilla, non-pkey mprotect (or we failed to
+	 * setup execute-only), inherit the pkey from the VMA we
+	 * are working on.
+	 */
+	return vma_pkey(vma);
 }
-- 
1.8.3.1

[RFC v3 15/23] powerpc: Program HPTE key protection bits

[Ram Pai]

Map the PTE protection key bits to the HPTE key protection bits,
while creating HPTE  entries.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/mmu-hash.h | 5 +++++
 arch/powerpc/include/asm/pkeys.h              | 7 +++++++
 arch/powerpc/mm/hash_utils_64.c               | 5 +++++
 3 files changed, 17 insertions(+)

diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index 6981a52..f7a6ed3 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -90,6 +90,8 @@
 #define HPTE_R_PP0		ASM_CONST(0x8000000000000000)
 #define HPTE_R_TS		ASM_CONST(0x4000000000000000)
 #define HPTE_R_KEY_HI		ASM_CONST(0x3000000000000000)
+#define HPTE_R_KEY_BIT0		ASM_CONST(0x2000000000000000)
+#define HPTE_R_KEY_BIT1		ASM_CONST(0x1000000000000000)
 #define HPTE_R_RPN_SHIFT	12
 #define HPTE_R_RPN		ASM_CONST(0x0ffffffffffff000)
 #define HPTE_R_RPN_3_0		ASM_CONST(0x01fffffffffff000)
@@ -104,6 +106,9 @@
 #define HPTE_R_C		ASM_CONST(0x0000000000000080)
 #define HPTE_R_R		ASM_CONST(0x0000000000000100)
 #define HPTE_R_KEY_LO		ASM_CONST(0x0000000000000e00)
+#define HPTE_R_KEY_BIT2		ASM_CONST(0x0000000000000800)
+#define HPTE_R_KEY_BIT3		ASM_CONST(0x0000000000000400)
+#define HPTE_R_KEY_BIT4		ASM_CONST(0x0000000000000200)
 
 #define HPTE_V_1TB_SEG		ASM_CONST(0x4000000000000000)
 #define HPTE_V_VRMA_MASK	ASM_CONST(0x4001ffffff000000)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 0f3dca8..af3882f 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -27,6 +27,13 @@
 		((vm_flags & VM_PKEY_BIT3) ? H_PAGE_PKEY_BIT1 : 0x0UL) |     \
 		((vm_flags & VM_PKEY_BIT4) ? H_PAGE_PKEY_BIT0 : 0x0UL))
 
+#define pte_to_hpte_pkey_bits(pteflags)	\
+	(((pteflags & H_PAGE_PKEY_BIT0) ? HPTE_R_KEY_BIT0 : 0x0UL) |	\
+	((pteflags & H_PAGE_PKEY_BIT1) ? HPTE_R_KEY_BIT1 : 0x0UL) |	\
+	((pteflags & H_PAGE_PKEY_BIT2) ? HPTE_R_KEY_BIT2 : 0x0UL) |	\
+	((pteflags & H_PAGE_PKEY_BIT3) ? HPTE_R_KEY_BIT3 : 0x0UL) |	\
+	((pteflags & H_PAGE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL))
+
 /*
  * Bits are in BE format.
  * NOTE: key 31, 1, 0 are not used.
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index b3bc5d6..34bc94c 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -35,6 +35,7 @@
 #include <linux/memblock.h>
 #include <linux/context_tracking.h>
 #include <linux/libfdt.h>
+#include <linux/pkeys.h>
 
 #include <asm/debugfs.h>
 #include <asm/processor.h>
@@ -230,6 +231,10 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags)
 		 */
 		rflags |= HPTE_R_M;
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	rflags |= pte_to_hpte_pkey_bits(pteflags);
+#endif
+
 	return rflags;
 }
 
-- 
1.8.3.1

[RFC v3 16/23] powerpc: Macro the mask used for checking DSI exception

[Ram Pai]

Replace the magic number used to check for DSI exception
with a meaningful value.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/reg.h       | 7 ++++++-
 arch/powerpc/kernel/exceptions-64s.S | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 7e50e47..ba110dd 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -272,16 +272,21 @@
 #define SPRN_DAR	0x013	/* Data Address Register */
 #define SPRN_DBCR	0x136	/* e300 Data Breakpoint Control Reg */
 #define SPRN_DSISR	0x012	/* Data Storage Interrupt Status Register */
+#define   DSISR_BIT32		0x80000000	/* not defined */
 #define   DSISR_NOHPTE		0x40000000	/* no translation found */
+#define   DSISR_PAGEATTR_CONFLT	0x20000000	/* page attribute conflict */
+#define   DSISR_BIT35		0x10000000	/* not defined */
 #define   DSISR_PROTFAULT	0x08000000	/* protection fault */
 #define   DSISR_BADACCESS	0x04000000	/* bad access to CI or G */
 #define   DSISR_ISSTORE		0x02000000	/* access was a store */
 #define   DSISR_DABRMATCH	0x00400000	/* hit data breakpoint */
-#define   DSISR_NOSEGMENT	0x00200000	/* SLB miss */
 #define   DSISR_KEYFAULT	0x00200000	/* Key fault */
+#define   DSISR_BIT43		0x00100000	/* not defined */
 #define   DSISR_UNSUPP_MMU	0x00080000	/* Unsupported MMU config */
 #define   DSISR_SET_RC		0x00040000	/* Failed setting of R/C bits */
 #define   DSISR_PGDIRFAULT      0x00020000      /* Fault on page directory */
+#define   DSISR_PAGE_FAULT_MASK (DSISR_BIT32 | DSISR_PAGEATTR_CONFLT | \
+				DSISR_BADACCESS | DSISR_BIT43)
 #define SPRN_TBRL	0x10C	/* Time Base Read Lower Register (user, R/O) */
 #define SPRN_TBRU	0x10D	/* Time Base Read Upper Register (user, R/O) */
 #define SPRN_CIR	0x11B	/* Chip Information Register (hyper, R/0) */
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index ae418b8..3fd0528 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1411,7 +1411,7 @@ USE_TEXT_SECTION()
 	.balign	IFETCH_ALIGN_BYTES
 do_hash_page:
 #ifdef CONFIG_PPC_STD_MMU_64
-	andis.	r0,r4,0xa410		/* weird error? */
+	andis.	r0,r4,DSISR_PAGE_FAULT_MASK@h
 	bne-	handle_page_fault	/* if not, try to insert a HPTE */
 	andis.  r0,r4,DSISR_DABRMATCH@h
 	bne-    handle_dabr_fault
-- 
1.8.3.1

[RFC v3 17/23] powerpc: Handle exceptions caused by violation of pkey protection

[Ram Pai]

Handle Data and Instruction exceptions caused by memory
protection-key.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/mmu_context.h | 12 +++++
 arch/powerpc/include/asm/pkeys.h       |  9 ++++
 arch/powerpc/include/asm/reg.h         |  2 +-
 arch/powerpc/mm/fault.c                | 20 ++++++++
 arch/powerpc/mm/pkeys.c                | 90 ++++++++++++++++++++++++++++++++++
 5 files changed, 132 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index da7e943..71fffe0 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -175,11 +175,23 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
 {
 }
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+bool arch_pte_access_permitted(pte_t pte, bool write);
+bool arch_vma_access_permitted(struct vm_area_struct *vma,
+		bool write, bool execute, bool foreign);
+#else /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+static inline bool arch_pte_access_permitted(pte_t pte, bool write)
+{
+	/* by default, allow everything */
+	return true;
+}
 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 		bool write, bool execute, bool foreign)
 {
 	/* by default, allow everything */
 	return true;
 }
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 #endif /* __KERNEL__ */
 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index af3882f..a83722e 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -14,6 +14,15 @@
 			VM_PKEY_BIT3 | \
 			VM_PKEY_BIT4)
 
+static inline u16 pte_flags_to_pkey(unsigned long pte_flags)
+{
+	return ((pte_flags & H_PAGE_PKEY_BIT4) ? 0x1 : 0x0) |
+		((pte_flags & H_PAGE_PKEY_BIT3) ? 0x2 : 0x0) |
+		((pte_flags & H_PAGE_PKEY_BIT2) ? 0x4 : 0x0) |
+		((pte_flags & H_PAGE_PKEY_BIT1) ? 0x8 : 0x0) |
+		((pte_flags & H_PAGE_PKEY_BIT0) ? 0x10 : 0x0);
+}
+
 #define pkey_to_vmflag_bits(key) (((key & 0x1UL) ? VM_PKEY_BIT0 : 0x0UL) | \
 			((key & 0x2UL) ? VM_PKEY_BIT1 : 0x0UL) |	\
 			((key & 0x4UL) ? VM_PKEY_BIT2 : 0x0UL) |	\
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index ba110dd..6e2a860 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -286,7 +286,7 @@
 #define   DSISR_SET_RC		0x00040000	/* Failed setting of R/C bits */
 #define   DSISR_PGDIRFAULT      0x00020000      /* Fault on page directory */
 #define   DSISR_PAGE_FAULT_MASK (DSISR_BIT32 | DSISR_PAGEATTR_CONFLT | \
-				DSISR_BADACCESS | DSISR_BIT43)
+			DSISR_BADACCESS | DSISR_KEYFAULT | DSISR_BIT43)
 #define SPRN_TBRL	0x10C	/* Time Base Read Lower Register (user, R/O) */
 #define SPRN_TBRU	0x10D	/* Time Base Read Upper Register (user, R/O) */
 #define SPRN_CIR	0x11B	/* Chip Information Register (hyper, R/0) */
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 3a7d580..3d71984 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -261,6 +261,13 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
 	}
 #endif
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	if (error_code & DSISR_KEYFAULT) {
+		code = SEGV_PKUERR;
+		goto bad_area_nosemaphore;
+	}
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	/* We restore the interrupt state now */
 	if (!arch_irq_disabled_regs(regs))
 		local_irq_enable();
@@ -441,6 +448,19 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
 		WARN_ON_ONCE(error_code & DSISR_PROTFAULT);
 #endif /* CONFIG_PPC_STD_MMU */
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+					is_exec, 0)) {
+		code = SEGV_PKUERR;
+		goto bad_area;
+	}
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+	/* handle_mm_fault() needs to know if its a instruction access
+	 * fault.
+	 */
+	if (is_exec)
+		flags |= FAULT_FLAG_INSTRUCTION;
 	/*
 	 * If for any reason at all we couldn't handle the fault,
 	 * make sure we exit gracefully rather than endlessly redo
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index 11a32b3..439241a 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -27,6 +27,37 @@ static inline bool pkey_allows_readwrite(int pkey)
 	return !(read_amr() & ((AMR_AD_BIT|AMR_WD_BIT) << pkey_shift));
 }
 
+static inline bool pkey_allows_read(int pkey)
+{
+	int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+	if (!(read_uamor() & (0x3ul << pkey_shift)))
+		return true;
+
+	return !(read_amr() & (AMR_AD_BIT << pkey_shift));
+}
+
+static inline bool pkey_allows_write(int pkey)
+{
+	int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+	if (!(read_uamor() & (0x3ul << pkey_shift)))
+		return true;
+
+	return !(read_amr() & (AMR_WD_BIT << pkey_shift));
+}
+
+static inline bool pkey_allows_execute(int pkey)
+{
+	int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+	if (!(read_uamor() & (0x3ul << pkey_shift)))
+		return true;
+
+	return !(read_iamr() & (IAMR_EX_BIT << pkey_shift));
+}
+
+
 /*
  * set the access right in AMR IAMR and UAMOR register
  * for @pkey to that specified in @init_val.
@@ -175,3 +206,62 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
 	 */
 	return vma_pkey(vma);
 }
+
+bool arch_pte_access_permitted(pte_t pte, bool write)
+{
+	int pkey = pte_flags_to_pkey(pte_val(pte));
+
+	if (!pkey_allows_read(pkey))
+		return false;
+	if (write && !pkey_allows_write(pkey))
+		return false;
+	return true;
+}
+
+/*
+ * We only want to enforce protection keys on the current process
+ * because we effectively have no access to AMR/IAMR for other
+ * processes or any way to tell *which * AMR/IAMR in a threaded
+ * process we could use.
+ *
+ * So do not enforce things if the VMA is not from the current
+ * mm, or if we are in a kernel thread.
+ */
+static inline bool vma_is_foreign(struct vm_area_struct *vma)
+{
+	if (!current->mm)
+		return true;
+	/*
+	 * if the VMA is from another process, then AMR/IAMR has no
+	 * relevance and should not be enforced.
+	 */
+	if (current->mm != vma->vm_mm)
+		return true;
+
+	return false;
+}
+
+bool arch_vma_access_permitted(struct vm_area_struct *vma,
+		bool write, bool execute, bool foreign)
+{
+	int pkey;
+	/* allow access if the VMA is not one from this process */
+	if (foreign || vma_is_foreign(vma))
+		return true;
+
+	pkey = vma_pkey(vma);
+
+	if (!pkey)
+		return true;
+
+	if (execute)
+		return pkey_allows_execute(pkey);
+
+	if (!pkey_allows_read(pkey))
+		return false;
+
+	if (write)
+		return pkey_allows_write(pkey);
+
+	return true;
+}
-- 
1.8.3.1

[RFC v3 18/23] powerpc: Deliver SEGV signal on pkey violation

[Ram Pai]

The value of the AMR register at the time of exception
is made available in gp_regs[PT_AMR] of the siginfo.

This field can be used to reprogram the permission bits of
any valid pkey.

Similarly the value of the pkey, whose protection got violated,
is made available at si_pkey field of the siginfo structure.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 arch/powerpc/include/asm/paca.h        |  1 +
 arch/powerpc/include/uapi/asm/ptrace.h |  3 ++-
 arch/powerpc/kernel/asm-offsets.c      |  5 ++++
 arch/powerpc/kernel/exceptions-64s.S   | 16 +++++++++--
 arch/powerpc/kernel/signal_32.c        | 14 ++++++++++
 arch/powerpc/kernel/signal_64.c        | 14 ++++++++++
 arch/powerpc/kernel/traps.c            | 49 ++++++++++++++++++++++++++++++++++
 arch/powerpc/mm/fault.c                |  2 ++
 8 files changed, 101 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 1c09f8f..a41afd3 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -92,6 +92,7 @@ struct paca_struct {
 	struct dtl_entry *dispatch_log_end;
 #endif /* CONFIG_PPC_STD_MMU_64 */
 	u64 dscr_default;		/* per-CPU default DSCR */
+	u64 paca_amr;			/* value of amr at exception */
 
 #ifdef CONFIG_PPC_STD_MMU_64
 	/*
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index 8036b38..7ec2428 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -108,8 +108,9 @@ struct pt_regs {
 #define PT_DAR	41
 #define PT_DSISR 42
 #define PT_RESULT 43
-#define PT_DSCR 44
 #define PT_REGS_COUNT 44
+#define PT_DSCR 44
+#define PT_AMR	45
 
 #define PT_FPR0	48	/* each FP reg occupies 2 slots in this space */
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 709e234..17f5d8a 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -241,6 +241,11 @@ int main(void)
 	OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
 	OFFSET(PACAKEXECSTATE, paca_struct, kexec_state);
 	OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default);
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	OFFSET(PACA_AMR, paca_struct, paca_amr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime);
 	OFFSET(ACCOUNT_STARTTIME_USER, paca_struct, accounting.starttime_user);
 	OFFSET(ACCOUNT_USER_TIME, paca_struct, accounting.utime);
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 3fd0528..a4de1b4 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -493,9 +493,15 @@ EXC_COMMON_BEGIN(data_access_common)
 	ld	r12,_MSR(r1)
 	ld	r3,PACA_EXGEN+EX_DAR(r13)
 	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
-	li	r5,0x300
 	std	r3,_DAR(r1)
 	std	r4,_DSISR(r1)
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	andis.  r0,r4,DSISR_KEYFAULT@h /* save AMR only if its a key fault */
+	beq+	1f
+	mfspr	r5,SPRN_AMR
+	std	r5,PACA_AMR(r13)
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+1:	li	r5,0x300
 BEGIN_MMU_FTR_SECTION
 	b	do_hash_page		/* Try to handle as hpte fault */
 MMU_FTR_SECTION_ELSE
@@ -561,9 +567,15 @@ EXC_COMMON_BEGIN(instruction_access_common)
 	ld	r12,_MSR(r1)
 	ld	r3,_NIP(r1)
 	andis.	r4,r12,0x5820
-	li	r5,0x400
 	std	r3,_DAR(r1)
 	std	r4,_DSISR(r1)
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	andis.  r0,r4,DSISR_KEYFAULT@h /* save AMR only if its a key fault */
+	beq+	1f
+	mfspr	r5,SPRN_AMR
+	std	r5,PACA_AMR(r13)
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+1:	li	r5,0x400
 BEGIN_MMU_FTR_SECTION
 	b	do_hash_page		/* Try to handle as hpte fault */
 MMU_FTR_SECTION_ELSE
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 97bb138..059766a 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -500,6 +500,11 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
 				   (unsigned long) &frame->tramp[2]);
 	}
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	if (__put_user(get_paca()->paca_amr, &frame->mc_gregs[PT_AMR]))
+		return 1;
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	return 0;
 }
 
@@ -661,6 +666,9 @@ static long restore_user_regs(struct pt_regs *regs,
 	long err;
 	unsigned int save_r2 = 0;
 	unsigned long msr;
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	unsigned long amr;
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
 #ifdef CONFIG_VSX
 	int i;
 #endif
@@ -750,6 +758,12 @@ static long restore_user_regs(struct pt_regs *regs,
 		return 1;
 #endif /* CONFIG_SPE */
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	err |= __get_user(amr, &sr->mc_gregs[PT_AMR]);
+	if (!err && amr != get_paca()->paca_amr)
+		write_amr(amr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	return 0;
 }
 
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index c83c115..35df2e4 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -174,6 +174,10 @@ static long setup_sigcontext(struct sigcontext __user *sc,
 	if (set != NULL)
 		err |=  __put_user(set->sig[0], &sc->oldmask);
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	err |= __put_user(get_paca()->paca_amr, &sc->gp_regs[PT_AMR]);
+#endif /*  CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	return err;
 }
 
@@ -327,6 +331,9 @@ static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
 	unsigned long save_r13 = 0;
 	unsigned long msr;
 	struct pt_regs *regs = tsk->thread.regs;
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	unsigned long amr;
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
 #ifdef CONFIG_VSX
 	int i;
 #endif
@@ -406,6 +413,13 @@ static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
 			tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
 	}
 #endif
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	err |= __get_user(amr, &sc->gp_regs[PT_AMR]);
+	if (!err && amr != get_paca()->paca_amr)
+		write_amr(amr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	return err;
 }
 
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d4e545d..cc4bde8b 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -20,6 +20,7 @@
 #include <linux/sched/debug.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
+#include <linux/pkeys.h>
 #include <linux/stddef.h>
 #include <linux/unistd.h>
 #include <linux/ptrace.h>
@@ -247,6 +248,49 @@ void user_single_step_siginfo(struct task_struct *tsk,
 	info->si_addr = (void __user *)regs->nip;
 }
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+static void fill_sig_info_pkey(int si_code, siginfo_t *info, unsigned long addr)
+{
+	struct vm_area_struct *vma;
+
+	/* Fault not from Protection Keys: nothing to do */
+	if (si_code != SEGV_PKUERR)
+		return;
+
+	down_read(&current->mm->mmap_sem);
+	/*
+	 * we could be racing with pkey_mprotect().
+	 * If pkey_mprotect() wins the key value could
+	 * get modified...xxx
+	 */
+	vma = find_vma(current->mm, addr);
+	up_read(&current->mm->mmap_sem);
+
+	/*
+	 * force_sig_info_fault() is called from a number of
+	 * contexts, some of which have a VMA and some of which
+	 * do not.  The Pkey-fault handing happens after we have a
+	 * valid VMA, so we should never reach this without a
+	 * valid VMA.
+	 */
+	if (!vma) {
+		WARN_ONCE(1, "Pkey fault with no VMA passed in");
+		info->si_pkey = 0;
+		return;
+	}
+
+	/*
+	 * We could report the incorrect key because of the reason
+	 * explained above.
+	 *
+	 * si_pkey should be thought off as a strong hint, but not
+	 * an absolutely guarantee because of the race explained
+	 * above.
+	 */
+	info->si_pkey = vma_pkey(vma);
+}
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
 {
 	siginfo_t info;
@@ -274,6 +318,11 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
 	info.si_signo = signr;
 	info.si_code = code;
 	info.si_addr = (void __user *) addr;
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	fill_sig_info_pkey(code, &info, addr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
 	force_sig_info(signr, &info, current);
 }
 
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 3d71984..0780a53 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -451,6 +451,8 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
 #ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
 	if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
 					is_exec, 0)) {
+		/* our caller may not have saved the amr. Lets save it */
+		get_paca()->paca_amr = read_amr();
 		code = SEGV_PKUERR;
 		goto bad_area;
 	}
-- 
1.8.3.1

[RFC v3 19/23] selftest: Move protecton key selftest to arch neutral directory

[Ram Pai]

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 tools/testing/selftests/vm/Makefile           |    1 +
 tools/testing/selftests/vm/pkey-helpers.h     |  219 ++++
 tools/testing/selftests/vm/protection_keys.c  | 1395 +++++++++++++++++++++++++
 tools/testing/selftests/x86/Makefile          |    2 +-
 tools/testing/selftests/x86/pkey-helpers.h    |  219 ----
 tools/testing/selftests/x86/protection_keys.c | 1395 -------------------------
 6 files changed, 1616 insertions(+), 1615 deletions(-)
 create mode 100644 tools/testing/selftests/vm/pkey-helpers.h
 create mode 100644 tools/testing/selftests/vm/protection_keys.c
 delete mode 100644 tools/testing/selftests/x86/pkey-helpers.h
 delete mode 100644 tools/testing/selftests/x86/protection_keys.c

diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index cbb29e4..1d32f78 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -17,6 +17,7 @@ TEST_GEN_FILES += transhuge-stress
 TEST_GEN_FILES += userfaultfd
 TEST_GEN_FILES += mlock-random-test
 TEST_GEN_FILES += virtual_address_range
+TEST_GEN_FILES += protection_keys
 
 TEST_PROGS := run_vmtests
 
diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
new file mode 100644
index 0000000..b202939
--- /dev/null
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -0,0 +1,219 @@
+#ifndef _PKEYS_HELPER_H
+#define _PKEYS_HELPER_H
+#define _GNU_SOURCE
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+
+#define NR_PKEYS 16
+#define PKRU_BITS_PER_PKEY 2
+
+#ifndef DEBUG_LEVEL
+#define DEBUG_LEVEL 0
+#endif
+#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
+extern int dprint_in_signal;
+extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+static inline void sigsafe_printf(const char *format, ...)
+{
+	va_list ap;
+
+	va_start(ap, format);
+	if (!dprint_in_signal) {
+		vprintf(format, ap);
+	} else {
+		int len = vsnprintf(dprint_in_signal_buffer,
+				    DPRINT_IN_SIGNAL_BUF_SIZE,
+				    format, ap);
+		/*
+		 * len is amount that would have been printed,
+		 * but actual write is truncated at BUF_SIZE.
+		 */
+		if (len > DPRINT_IN_SIGNAL_BUF_SIZE)
+			len = DPRINT_IN_SIGNAL_BUF_SIZE;
+		write(1, dprint_in_signal_buffer, len);
+	}
+	va_end(ap);
+}
+#define dprintf_level(level, args...) do {	\
+	if (level <= DEBUG_LEVEL)		\
+		sigsafe_printf(args);		\
+	fflush(NULL);				\
+} while (0)
+#define dprintf0(args...) dprintf_level(0, args)
+#define dprintf1(args...) dprintf_level(1, args)
+#define dprintf2(args...) dprintf_level(2, args)
+#define dprintf3(args...) dprintf_level(3, args)
+#define dprintf4(args...) dprintf_level(4, args)
+
+extern unsigned int shadow_pkru;
+static inline unsigned int __rdpkru(void)
+{
+	unsigned int eax, edx;
+	unsigned int ecx = 0;
+	unsigned int pkru;
+
+	asm volatile(".byte 0x0f,0x01,0xee\n\t"
+		     : "=a" (eax), "=d" (edx)
+		     : "c" (ecx));
+	pkru = eax;
+	return pkru;
+}
+
+static inline unsigned int _rdpkru(int line)
+{
+	unsigned int pkru = __rdpkru();
+
+	dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
+			line, pkru, shadow_pkru);
+	assert(pkru == shadow_pkru);
+
+	return pkru;
+}
+
+#define rdpkru() _rdpkru(__LINE__)
+
+static inline void __wrpkru(unsigned int pkru)
+{
+	unsigned int eax = pkru;
+	unsigned int ecx = 0;
+	unsigned int edx = 0;
+
+	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+	asm volatile(".byte 0x0f,0x01,0xef\n\t"
+		     : : "a" (eax), "c" (ecx), "d" (edx));
+	assert(pkru == __rdpkru());
+}
+
+static inline void wrpkru(unsigned int pkru)
+{
+	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+	/* will do the shadow check for us: */
+	rdpkru();
+	__wrpkru(pkru);
+	shadow_pkru = pkru;
+	dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
+}
+
+/*
+ * These are technically racy. since something could
+ * change PKRU between the read and the write.
+ */
+static inline void __pkey_access_allow(int pkey, int do_allow)
+{
+	unsigned int pkru = rdpkru();
+	int bit = pkey * 2;
+
+	if (do_allow)
+		pkru &= (1<<bit);
+	else
+		pkru |= (1<<bit);
+
+	dprintf4("pkru now: %08x\n", rdpkru());
+	wrpkru(pkru);
+}
+
+static inline void __pkey_write_allow(int pkey, int do_allow_write)
+{
+	long pkru = rdpkru();
+	int bit = pkey * 2 + 1;
+
+	if (do_allow_write)
+		pkru &= (1<<bit);
+	else
+		pkru |= (1<<bit);
+
+	wrpkru(pkru);
+	dprintf4("pkru now: %08x\n", rdpkru());
+}
+
+#define PROT_PKEY0     0x10            /* protection key value (bit 0) */
+#define PROT_PKEY1     0x20            /* protection key value (bit 1) */
+#define PROT_PKEY2     0x40            /* protection key value (bit 2) */
+#define PROT_PKEY3     0x80            /* protection key value (bit 3) */
+
+#define PAGE_SIZE 4096
+#define MB	(1<<20)
+
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+		unsigned int *ecx, unsigned int *edx)
+{
+	/* ecx is often an input as well as an output. */
+	asm volatile(
+		"cpuid;"
+		: "=a" (*eax),
+		  "=b" (*ebx),
+		  "=c" (*ecx),
+		  "=d" (*edx)
+		: "0" (*eax), "2" (*ecx));
+}
+
+/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
+#define X86_FEATURE_PKU        (1<<3) /* Protection Keys for Userspace */
+#define X86_FEATURE_OSPKE      (1<<4) /* OS Protection Keys Enable */
+
+static inline int cpu_has_pku(void)
+{
+	unsigned int eax;
+	unsigned int ebx;
+	unsigned int ecx;
+	unsigned int edx;
+
+	eax = 0x7;
+	ecx = 0x0;
+	__cpuid(&eax, &ebx, &ecx, &edx);
+
+	if (!(ecx & X86_FEATURE_PKU)) {
+		dprintf2("cpu does not have PKU\n");
+		return 0;
+	}
+	if (!(ecx & X86_FEATURE_OSPKE)) {
+		dprintf2("cpu does not have OSPKE\n");
+		return 0;
+	}
+	return 1;
+}
+
+#define XSTATE_PKRU_BIT	(9)
+#define XSTATE_PKRU	0x200
+
+int pkru_xstate_offset(void)
+{
+	unsigned int eax;
+	unsigned int ebx;
+	unsigned int ecx;
+	unsigned int edx;
+	int xstate_offset;
+	int xstate_size;
+	unsigned long XSTATE_CPUID = 0xd;
+	int leaf;
+
+	/* assume that XSTATE_PKRU is set in XCR0 */
+	leaf = XSTATE_PKRU_BIT;
+	{
+		eax = XSTATE_CPUID;
+		ecx = leaf;
+		__cpuid(&eax, &ebx, &ecx, &edx);
+
+		if (leaf == XSTATE_PKRU_BIT) {
+			xstate_offset = ebx;
+			xstate_size = eax;
+		}
+	}
+
+	if (xstate_size == 0) {
+		printf("could not find size/offset of PKRU in xsave state\n");
+		return 0;
+	}
+
+	return xstate_offset;
+}
+
+#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
new file mode 100644
index 0000000..3237bc0
--- /dev/null
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -0,0 +1,1395 @@
+/*
+ * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
+ *
+ * There are examples in here of:
+ *  * how to set protection keys on memory
+ *  * how to set/clear bits in PKRU (the rights register)
+ *  * how to handle SEGV_PKRU signals and extract pkey-relevant
+ *    information from the siginfo
+ *
+ * Things to add:
+ *	make sure KSM and KSM COW breaking works
+ *	prefault pages in at malloc, or not
+ *	protect MPX bounds tables with protection keys?
+ *	make sure VMA splitting/merging is working correctly
+ *	OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
+ *	look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
+ *	do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
+ *
+ * Compile like this:
+ *	gcc      -o protection_keys    -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ *	gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ */
+#define _GNU_SOURCE
+#include <errno.h>
+#include <linux/futex.h>
+#include <sys/time.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+#include <setjmp.h>
+
+#include "pkey-helpers.h"
+
+int iteration_nr = 1;
+int test_nr;
+
+unsigned int shadow_pkru;
+
+#define HPAGE_SIZE	(1UL<<21)
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+#define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
+#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
+#define ALIGN_PTR_UP(p, ptr_align_to)	((typeof(p))ALIGN_UP((unsigned long)(p),	ptr_align_to))
+#define ALIGN_PTR_DOWN(p, ptr_align_to)	((typeof(p))ALIGN_DOWN((unsigned long)(p),	ptr_align_to))
+#define __stringify_1(x...)     #x
+#define __stringify(x...)       __stringify_1(x)
+
+#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+
+int dprint_in_signal;
+char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+
+extern void abort_hooks(void);
+#define pkey_assert(condition) do {		\
+	if (!(condition)) {			\
+		dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
+				__FILE__, __LINE__,	\
+				test_nr, iteration_nr);	\
+		dprintf0("errno at assert: %d", errno);	\
+		abort_hooks();			\
+		assert(condition);		\
+	}					\
+} while (0)
+#define raw_assert(cond) assert(cond)
+
+void cat_into_file(char *str, char *file)
+{
+	int fd = open(file, O_RDWR);
+	int ret;
+
+	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
+	/*
+	 * these need to be raw because they are called under
+	 * pkey_assert()
+	 */
+	raw_assert(fd >= 0);
+	ret = write(fd, str, strlen(str));
+	if (ret != strlen(str)) {
+		perror("write to file failed");
+		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
+		raw_assert(0);
+	}
+	close(fd);
+}
+
+#if CONTROL_TRACING > 0
+static int warned_tracing;
+int tracing_root_ok(void)
+{
+	if (geteuid() != 0) {
+		if (!warned_tracing)
+			fprintf(stderr, "WARNING: not run as root, "
+					"can not do tracing control\n");
+		warned_tracing = 1;
+		return 0;
+	}
+	return 1;
+}
+#endif
+
+void tracing_on(void)
+{
+#if CONTROL_TRACING > 0
+#define TRACEDIR "/sys/kernel/debug/tracing"
+	char pidstr[32];
+
+	if (!tracing_root_ok())
+		return;
+
+	sprintf(pidstr, "%d", getpid());
+	cat_into_file("0", TRACEDIR "/tracing_on");
+	cat_into_file("\n", TRACEDIR "/trace");
+	if (1) {
+		cat_into_file("function_graph", TRACEDIR "/current_tracer");
+		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
+	} else {
+		cat_into_file("nop", TRACEDIR "/current_tracer");
+	}
+	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
+	cat_into_file("1", TRACEDIR "/tracing_on");
+	dprintf1("enabled tracing\n");
+#endif
+}
+
+void tracing_off(void)
+{
+#if CONTROL_TRACING > 0
+	if (!tracing_root_ok())
+		return;
+	cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
+#endif
+}
+
+void abort_hooks(void)
+{
+	fprintf(stderr, "running %s()...\n", __func__);
+	tracing_off();
+#ifdef SLEEP_ON_ABORT
+	sleep(SLEEP_ON_ABORT);
+#endif
+}
+
+static inline void __page_o_noops(void)
+{
+	/* 8-bytes of instruction * 512 bytes = 1 page */
+	asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
+}
+
+/*
+ * This attempts to have roughly a page of instructions followed by a few
+ * instructions that do a write, and another page of instructions.  That
+ * way, we are pretty sure that the write is in the second page of
+ * instructions and has at least a page of padding behind it.
+ *
+ * *That* lets us be sure to madvise() away the write instruction, which
+ * will then fault, which makes sure that the fault code handles
+ * execute-only memory properly.
+ */
+__attribute__((__aligned__(PAGE_SIZE)))
+void lots_o_noops_around_write(int *write_to_me)
+{
+	dprintf3("running %s()\n", __func__);
+	__page_o_noops();
+	/* Assume this happens in the second page of instructions: */
+	*write_to_me = __LINE__;
+	/* pad out by another page: */
+	__page_o_noops();
+	dprintf3("%s() done\n", __func__);
+}
+
+/* Define some kernel-like types */
+#define  u8 uint8_t
+#define u16 uint16_t
+#define u32 uint32_t
+#define u64 uint64_t
+
+#ifdef __i386__
+#define SYS_mprotect_key 380
+#define SYS_pkey_alloc	 381
+#define SYS_pkey_free	 382
+#define REG_IP_IDX REG_EIP
+#define si_pkey_offset 0x14
+#else
+#define SYS_mprotect_key 329
+#define SYS_pkey_alloc	 330
+#define SYS_pkey_free	 331
+#define REG_IP_IDX REG_RIP
+#define si_pkey_offset 0x20
+#endif
+
+void dump_mem(void *dumpme, int len_bytes)
+{
+	char *c = (void *)dumpme;
+	int i;
+
+	for (i = 0; i < len_bytes; i += sizeof(u64)) {
+		u64 *ptr = (u64 *)(c + i);
+		dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
+	}
+}
+
+#define __SI_FAULT      (3 << 16)
+#define SEGV_BNDERR     (__SI_FAULT|3)  /* failed address bound checks */
+#define SEGV_PKUERR     (__SI_FAULT|4)
+
+static char *si_code_str(int si_code)
+{
+	if (si_code & SEGV_MAPERR)
+		return "SEGV_MAPERR";
+	if (si_code & SEGV_ACCERR)
+		return "SEGV_ACCERR";
+	if (si_code & SEGV_BNDERR)
+		return "SEGV_BNDERR";
+	if (si_code & SEGV_PKUERR)
+		return "SEGV_PKUERR";
+	return "UNKNOWN";
+}
+
+int pkru_faults;
+int last_si_pkey = -1;
+void signal_handler(int signum, siginfo_t *si, void *vucontext)
+{
+	ucontext_t *uctxt = vucontext;
+	int trapno;
+	unsigned long ip;
+	char *fpregs;
+	u32 *pkru_ptr;
+	u64 si_pkey;
+	u32 *si_pkey_ptr;
+	int pkru_offset;
+	fpregset_t fpregset;
+
+	dprint_in_signal = 1;
+	dprintf1(">>>>===============SIGSEGV============================\n");
+	dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
+			__rdpkru(), shadow_pkru);
+
+	trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
+	ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
+	fpregset = uctxt->uc_mcontext.fpregs;
+	fpregs = (void *)fpregset;
+
+	dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
+			trapno, ip, si_code_str(si->si_code), si->si_code);
+#ifdef __i386__
+	/*
+	 * 32-bit has some extra padding so that userspace can tell whether
+	 * the XSTATE header is present in addition to the "legacy" FPU
+	 * state.  We just assume that it is here.
+	 */
+	fpregs += 0x70;
+#endif
+	pkru_offset = pkru_xstate_offset();
+	pkru_ptr = (void *)(&fpregs[pkru_offset]);
+
+	dprintf1("siginfo: %p\n", si);
+	dprintf1(" fpregs: %p\n", fpregs);
+	/*
+	 * If we got a PKRU fault, we *HAVE* to have at least one bit set in
+	 * here.
+	 */
+	dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
+	if (DEBUG_LEVEL > 4)
+		dump_mem(pkru_ptr - 128, 256);
+	pkey_assert(*pkru_ptr);
+
+	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
+	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
+	dump_mem(si_pkey_ptr - 8, 24);
+	si_pkey = *si_pkey_ptr;
+	pkey_assert(si_pkey < NR_PKEYS);
+	last_si_pkey = si_pkey;
+
+	if ((si->si_code == SEGV_MAPERR) ||
+	    (si->si_code == SEGV_ACCERR) ||
+	    (si->si_code == SEGV_BNDERR)) {
+		printf("non-PK si_code, exiting...\n");
+		exit(4);
+	}
+
+	dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
+	/* need __rdpkru() version so we do not do shadow_pkru checking */
+	dprintf1("signal pkru from  pkru: %08x\n", __rdpkru());
+	dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
+	*(u64 *)pkru_ptr = 0x00000000;
+	dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
+	pkru_faults++;
+	dprintf1("<<<<==================================================\n");
+	return;
+	if (trapno == 14) {
+		fprintf(stderr,
+			"ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
+			trapno, ip);
+		fprintf(stderr, "si_addr %p\n", si->si_addr);
+		fprintf(stderr, "REG_ERR: %lx\n",
+				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
+		exit(1);
+	} else {
+		fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
+		fprintf(stderr, "si_addr %p\n", si->si_addr);
+		fprintf(stderr, "REG_ERR: %lx\n",
+				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
+		exit(2);
+	}
+	dprint_in_signal = 0;
+}
+
+int wait_all_children(void)
+{
+	int status;
+	return waitpid(-1, &status, 0);
+}
+
+void sig_chld(int x)
+{
+	dprint_in_signal = 1;
+	dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
+	dprint_in_signal = 0;
+}
+
+void setup_sigsegv_handler(void)
+{
+	int r, rs;
+	struct sigaction newact;
+	struct sigaction oldact;
+
+	/* #PF is mapped to sigsegv */
+	int signum  = SIGSEGV;
+
+	newact.sa_handler = 0;
+	newact.sa_sigaction = signal_handler;
+
+	/*sigset_t - signals to block while in the handler */
+	/* get the old signal mask. */
+	rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
+	pkey_assert(rs == 0);
+
+	/* call sa_sigaction, not sa_handler*/
+	newact.sa_flags = SA_SIGINFO;
+
+	newact.sa_restorer = 0;  /* void(*)(), obsolete */
+	r = sigaction(signum, &newact, &oldact);
+	r = sigaction(SIGALRM, &newact, &oldact);
+	pkey_assert(r == 0);
+}
+
+void setup_handlers(void)
+{
+	signal(SIGCHLD, &sig_chld);
+	setup_sigsegv_handler();
+}
+
+pid_t fork_lazy_child(void)
+{
+	pid_t forkret;
+
+	forkret = fork();
+	pkey_assert(forkret >= 0);
+	dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
+
+	if (!forkret) {
+		/* in the child */
+		while (1) {
+			dprintf1("child sleeping...\n");
+			sleep(30);
+		}
+	}
+	return forkret;
+}
+
+void davecmp(void *_a, void *_b, int len)
+{
+	int i;
+	unsigned long *a = _a;
+	unsigned long *b = _b;
+
+	for (i = 0; i < len / sizeof(*a); i++) {
+		if (a[i] == b[i])
+			continue;
+
+		dprintf3("[%3d]: a: %016lx b: %016lx\n", i, a[i], b[i]);
+	}
+}
+
+void dumpit(char *f)
+{
+	int fd = open(f, O_RDONLY);
+	char buf[100];
+	int nr_read;
+
+	dprintf2("maps fd: %d\n", fd);
+	do {
+		nr_read = read(fd, &buf[0], sizeof(buf));
+		write(1, buf, nr_read);
+	} while (nr_read > 0);
+	close(fd);
+}
+
+#define PKEY_DISABLE_ACCESS    0x1
+#define PKEY_DISABLE_WRITE     0x2
+
+u32 pkey_get(int pkey, unsigned long flags)
+{
+	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+	u32 pkru = __rdpkru();
+	u32 shifted_pkru;
+	u32 masked_pkru;
+
+	dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
+			__func__, pkey, flags, 0, 0);
+	dprintf2("%s() raw pkru: %x\n", __func__, pkru);
+
+	shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
+	dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
+	masked_pkru = shifted_pkru & mask;
+	dprintf2("%s() masked  pkru: %x\n", __func__, masked_pkru);
+	/*
+	 * shift down the relevant bits to the lowest two, then
+	 * mask off all the other high bits.
+	 */
+	return masked_pkru;
+}
+
+int pkey_set(int pkey, unsigned long rights, unsigned long flags)
+{
+	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+	u32 old_pkru = __rdpkru();
+	u32 new_pkru;
+
+	/* make sure that 'rights' only contains the bits we expect: */
+	assert(!(rights & ~mask));
+
+	/* copy old pkru */
+	new_pkru = old_pkru;
+	/* mask out bits from pkey in old value: */
+	new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
+	/* OR in new bits for pkey: */
+	new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
+
+	__wrpkru(new_pkru);
+
+	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
+			__func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
+	return 0;
+}
+
+void pkey_disable_set(int pkey, int flags)
+{
+	unsigned long syscall_flags = 0;
+	int ret;
+	int pkey_rights;
+	u32 orig_pkru = rdpkru();
+
+	dprintf1("START->%s(%d, 0x%x)\n", __func__,
+		pkey, flags);
+	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+	pkey_rights = pkey_get(pkey, syscall_flags);
+
+	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+			pkey, pkey, pkey_rights);
+	pkey_assert(pkey_rights >= 0);
+
+	pkey_rights |= flags;
+
+	ret = pkey_set(pkey, pkey_rights, syscall_flags);
+	assert(!ret);
+	/*pkru and flags have the same format */
+	shadow_pkru |= flags << (pkey * 2);
+	dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
+
+	pkey_assert(ret >= 0);
+
+	pkey_rights = pkey_get(pkey, syscall_flags);
+	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+			pkey, pkey, pkey_rights);
+
+	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+	if (flags)
+		pkey_assert(rdpkru() > orig_pkru);
+	dprintf1("END<---%s(%d, 0x%x)\n", __func__,
+		pkey, flags);
+}
+
+void pkey_disable_clear(int pkey, int flags)
+{
+	unsigned long syscall_flags = 0;
+	int ret;
+	int pkey_rights = pkey_get(pkey, syscall_flags);
+	u32 orig_pkru = rdpkru();
+
+	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+			pkey, pkey, pkey_rights);
+	pkey_assert(pkey_rights >= 0);
+
+	pkey_rights |= flags;
+
+	ret = pkey_set(pkey, pkey_rights, 0);
+	/* pkru and flags have the same format */
+	shadow_pkru &= ~(flags << (pkey * 2));
+	pkey_assert(ret >= 0);
+
+	pkey_rights = pkey_get(pkey, syscall_flags);
+	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+			pkey, pkey, pkey_rights);
+
+	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+	if (flags)
+		assert(rdpkru() > orig_pkru);
+}
+
+void pkey_write_allow(int pkey)
+{
+	pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_write_deny(int pkey)
+{
+	pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_access_allow(int pkey)
+{
+	pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
+}
+void pkey_access_deny(int pkey)
+{
+	pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
+}
+
+int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+		unsigned long pkey)
+{
+	int sret;
+
+	dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
+			ptr, size, orig_prot, pkey);
+
+	errno = 0;
+	sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
+	if (errno) {
+		dprintf2("SYS_mprotect_key sret: %d\n", sret);
+		dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
+		dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
+		if (DEBUG_LEVEL >= 2)
+			perror("SYS_mprotect_pkey");
+	}
+	return sret;
+}
+
+int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
+{
+	int ret = syscall(SYS_pkey_alloc, flags, init_val);
+	dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
+			__func__, flags, init_val, ret, errno);
+	return ret;
+}
+
+int alloc_pkey(void)
+{
+	int ret;
+	unsigned long init_val = 0x0;
+
+	dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
+			__LINE__, __rdpkru(), shadow_pkru);
+	ret = sys_pkey_alloc(0, init_val);
+	/*
+	 * pkey_alloc() sets PKRU, so we need to reflect it in
+	 * shadow_pkru:
+	 */
+	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	if (ret) {
+		/* clear both the bits: */
+		shadow_pkru &= ~(0x3      << (ret * 2));
+		dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+				__LINE__, ret, __rdpkru(), shadow_pkru);
+		/*
+		 * move the new state in from init_val
+		 * (remember, we cheated and init_val == pkru format)
+		 */
+		shadow_pkru |=  (init_val << (ret * 2));
+	}
+	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
+	/* for shadow checking: */
+	rdpkru();
+	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	return ret;
+}
+
+int sys_pkey_free(unsigned long pkey)
+{
+	int ret = syscall(SYS_pkey_free, pkey);
+	dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
+	return ret;
+}
+
+/*
+ * I had a bug where pkey bits could be set by mprotect() but
+ * not cleared.  This ensures we get lots of random bit sets
+ * and clears on the vma and pte pkey bits.
+ */
+int alloc_random_pkey(void)
+{
+	int max_nr_pkey_allocs;
+	int ret;
+	int i;
+	int alloced_pkeys[NR_PKEYS];
+	int nr_alloced = 0;
+	int random_index;
+	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+
+	/* allocate every possible key and make a note of which ones we got */
+	max_nr_pkey_allocs = NR_PKEYS;
+	max_nr_pkey_allocs = 1;
+	for (i = 0; i < max_nr_pkey_allocs; i++) {
+		int new_pkey = alloc_pkey();
+		if (new_pkey < 0)
+			break;
+		alloced_pkeys[nr_alloced++] = new_pkey;
+	}
+
+	pkey_assert(nr_alloced > 0);
+	/* select a random one out of the allocated ones */
+	random_index = rand() % nr_alloced;
+	ret = alloced_pkeys[random_index];
+	/* now zero it out so we don't free it next */
+	alloced_pkeys[random_index] = 0;
+
+	/* go through the allocated ones that we did not want and free them */
+	for (i = 0; i < nr_alloced; i++) {
+		int free_ret;
+		if (!alloced_pkeys[i])
+			continue;
+		free_ret = sys_pkey_free(alloced_pkeys[i]);
+		pkey_assert(!free_ret);
+	}
+	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	return ret;
+}
+
+int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+		unsigned long pkey)
+{
+	int nr_iterations = random() % 100;
+	int ret;
+
+	while (0) {
+		int rpkey = alloc_random_pkey();
+		ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+				ptr, size, orig_prot, pkey, ret);
+		if (nr_iterations-- < 0)
+			break;
+
+		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+		sys_pkey_free(rpkey);
+		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	}
+	pkey_assert(pkey < NR_PKEYS);
+
+	ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+	dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+			ptr, size, orig_prot, pkey, ret);
+	pkey_assert(!ret);
+	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkru(), shadow_pkru);
+	return ret;
+}
+
+struct pkey_malloc_record {
+	void *ptr;
+	long size;
+};
+struct pkey_malloc_record *pkey_malloc_records;
+long nr_pkey_malloc_records;
+void record_pkey_malloc(void *ptr, long size)
+{
+	long i;
+	struct pkey_malloc_record *rec = NULL;
+
+	for (i = 0; i < nr_pkey_malloc_records; i++) {
+		rec = &pkey_malloc_records[i];
+		/* find a free record */
+		if (rec)
+			break;
+	}
+	if (!rec) {
+		/* every record is full */
+		size_t old_nr_records = nr_pkey_malloc_records;
+		size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
+		size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
+		dprintf2("new_nr_records: %zd\n", new_nr_records);
+		dprintf2("new_size: %zd\n", new_size);
+		pkey_malloc_records = realloc(pkey_malloc_records, new_size);
+		pkey_assert(pkey_malloc_records != NULL);
+		rec = &pkey_malloc_records[nr_pkey_malloc_records];
+		/*
+		 * realloc() does not initialize memory, so zero it from
+		 * the first new record all the way to the end.
+		 */
+		for (i = 0; i < new_nr_records - old_nr_records; i++)
+			memset(rec + i, 0, sizeof(*rec));
+	}
+	dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
+		(int)(rec - pkey_malloc_records), rec, ptr, size);
+	rec->ptr = ptr;
+	rec->size = size;
+	nr_pkey_malloc_records++;
+}
+
+void free_pkey_malloc(void *ptr)
+{
+	long i;
+	int ret;
+	dprintf3("%s(%p)\n", __func__, ptr);
+	for (i = 0; i < nr_pkey_malloc_records; i++) {
+		struct pkey_malloc_record *rec = &pkey_malloc_records[i];
+		dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
+				ptr, i, rec, rec->ptr, rec->size);
+		if ((ptr <  rec->ptr) ||
+		    (ptr >= rec->ptr + rec->size))
+			continue;
+
+		dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
+				ptr, i, rec, rec->ptr, rec->size);
+		nr_pkey_malloc_records--;
+		ret = munmap(rec->ptr, rec->size);
+		dprintf3("munmap ret: %d\n", ret);
+		pkey_assert(!ret);
+		dprintf3("clearing rec->ptr, rec: %p\n", rec);
+		rec->ptr = NULL;
+		dprintf3("done clearing rec->ptr, rec: %p\n", rec);
+		return;
+	}
+	pkey_assert(false);
+}
+
+
+void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
+{
+	void *ptr;
+	int ret;
+
+	rdpkru();
+	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+			size, prot, pkey);
+	pkey_assert(pkey < NR_PKEYS);
+	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+	pkey_assert(ptr != (void *)-1);
+	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+	pkey_assert(!ret);
+	record_pkey_malloc(ptr, size);
+	rdpkru();
+
+	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+	return ptr;
+}
+
+void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
+{
+	int ret;
+	void *ptr;
+
+	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+			size, prot, pkey);
+	/*
+	 * Guarantee we can fit at least one huge page in the resulting
+	 * allocation by allocating space for 2:
+	 */
+	size = ALIGN_UP(size, HPAGE_SIZE * 2);
+	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+	pkey_assert(ptr != (void *)-1);
+	record_pkey_malloc(ptr, size);
+	mprotect_pkey(ptr, size, prot, pkey);
+
+	dprintf1("unaligned ptr: %p\n", ptr);
+	ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
+	dprintf1("  aligned ptr: %p\n", ptr);
+	ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
+	dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
+	ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
+	dprintf1("MADV_WILLNEED ret: %d\n", ret);
+	memset(ptr, 0, HPAGE_SIZE);
+
+	dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
+	return ptr;
+}
+
+int hugetlb_setup_ok;
+#define GET_NR_HUGE_PAGES 10
+void setup_hugetlbfs(void)
+{
+	int err;
+	int fd;
+	char buf[] = "123";
+
+	if (geteuid() != 0) {
+		fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
+		return;
+	}
+
+	cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
+
+	/*
+	 * Now go make sure that we got the pages and that they
+	 * are 2M pages.  Someone might have made 1G the default.
+	 */
+	fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
+	if (fd < 0) {
+		perror("opening sysfs 2M hugetlb config");
+		return;
+	}
+
+	/* -1 to guarantee leaving the trailing \0 */
+	err = read(fd, buf, sizeof(buf)-1);
+	close(fd);
+	if (err <= 0) {
+		perror("reading sysfs 2M hugetlb config");
+		return;
+	}
+
+	if (atoi(buf) != GET_NR_HUGE_PAGES) {
+		fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
+			buf, GET_NR_HUGE_PAGES);
+		return;
+	}
+
+	hugetlb_setup_ok = 1;
+}
+
+void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
+{
+	void *ptr;
+	int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
+
+	if (!hugetlb_setup_ok)
+		return PTR_ERR_ENOTSUP;
+
+	dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
+	size = ALIGN_UP(size, HPAGE_SIZE * 2);
+	pkey_assert(pkey < NR_PKEYS);
+	ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
+	pkey_assert(ptr != (void *)-1);
+	mprotect_pkey(ptr, size, prot, pkey);
+
+	record_pkey_malloc(ptr, size);
+
+	dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
+	return ptr;
+}
+
+void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
+{
+	void *ptr;
+	int fd;
+
+	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+			size, prot, pkey);
+	pkey_assert(pkey < NR_PKEYS);
+	fd = open("/dax/foo", O_RDWR);
+	pkey_assert(fd >= 0);
+
+	ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
+	pkey_assert(ptr != (void *)-1);
+
+	mprotect_pkey(ptr, size, prot, pkey);
+
+	record_pkey_malloc(ptr, size);
+
+	dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
+	close(fd);
+	return ptr;
+}
+
+void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
+
+	malloc_pkey_with_mprotect,
+	malloc_pkey_anon_huge,
+	malloc_pkey_hugetlb
+/* can not do direct with the pkey_mprotect() API:
+	malloc_pkey_mmap_direct,
+	malloc_pkey_mmap_dax,
+*/
+};
+
+void *malloc_pkey(long size, int prot, u16 pkey)
+{
+	void *ret;
+	static int malloc_type;
+	int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
+
+	pkey_assert(pkey < NR_PKEYS);
+
+	while (1) {
+		pkey_assert(malloc_type < nr_malloc_types);
+
+		ret = pkey_malloc[malloc_type](size, prot, pkey);
+		pkey_assert(ret != (void *)-1);
+
+		malloc_type++;
+		if (malloc_type >= nr_malloc_types)
+			malloc_type = (random()%nr_malloc_types);
+
+		/* try again if the malloc_type we tried is unsupported */
+		if (ret == PTR_ERR_ENOTSUP)
+			continue;
+
+		break;
+	}
+
+	dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
+			size, prot, pkey, ret);
+	return ret;
+}
+
+int last_pkru_faults;
+void expected_pk_fault(int pkey)
+{
+	dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
+			__func__, last_pkru_faults, pkru_faults);
+	dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
+	pkey_assert(last_pkru_faults + 1 == pkru_faults);
+	pkey_assert(last_si_pkey == pkey);
+	/*
+	 * The signal handler shold have cleared out PKRU to let the
+	 * test program continue.  We now have to restore it.
+	 */
+	if (__rdpkru() != 0)
+		pkey_assert(0);
+
+	__wrpkru(shadow_pkru);
+	dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
+			__func__, shadow_pkru);
+	last_pkru_faults = pkru_faults;
+	last_si_pkey = -1;
+}
+
+void do_not_expect_pk_fault(void)
+{
+	pkey_assert(last_pkru_faults == pkru_faults);
+}
+
+int test_fds[10] = { -1 };
+int nr_test_fds;
+void __save_test_fd(int fd)
+{
+	pkey_assert(fd >= 0);
+	pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
+	test_fds[nr_test_fds] = fd;
+	nr_test_fds++;
+}
+
+int get_test_read_fd(void)
+{
+	int test_fd = open("/etc/passwd", O_RDONLY);
+	__save_test_fd(test_fd);
+	return test_fd;
+}
+
+void close_test_fds(void)
+{
+	int i;
+
+	for (i = 0; i < nr_test_fds; i++) {
+		if (test_fds[i] < 0)
+			continue;
+		close(test_fds[i]);
+		test_fds[i] = -1;
+	}
+	nr_test_fds = 0;
+}
+
+#define barrier() __asm__ __volatile__("": : :"memory")
+__attribute__((noinline)) int read_ptr(int *ptr)
+{
+	/*
+	 * Keep GCC from optimizing this away somehow
+	 */
+	barrier();
+	return *ptr;
+}
+
+void test_read_of_write_disabled_region(int *ptr, u16 pkey)
+{
+	int ptr_contents;
+
+	dprintf1("disabling write access to PKEY[1], doing read\n");
+	pkey_write_deny(pkey);
+	ptr_contents = read_ptr(ptr);
+	dprintf1("*ptr: %d\n", ptr_contents);
+	dprintf1("\n");
+}
+void test_read_of_access_disabled_region(int *ptr, u16 pkey)
+{
+	int ptr_contents;
+
+	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
+	rdpkru();
+	pkey_access_deny(pkey);
+	ptr_contents = read_ptr(ptr);
+	dprintf1("*ptr: %d\n", ptr_contents);
+	expected_pk_fault(pkey);
+}
+void test_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+	dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
+	pkey_write_deny(pkey);
+	*ptr = __LINE__;
+	expected_pk_fault(pkey);
+}
+void test_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+	dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
+	pkey_access_deny(pkey);
+	*ptr = __LINE__;
+	expected_pk_fault(pkey);
+}
+void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+	int ret;
+	int test_fd = get_test_read_fd();
+
+	dprintf1("disabling access to PKEY[%02d], "
+		 "having kernel read() to buffer\n", pkey);
+	pkey_access_deny(pkey);
+	ret = read(test_fd, ptr, 1);
+	dprintf1("read ret: %d\n", ret);
+	pkey_assert(ret);
+}
+void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+	int ret;
+	int test_fd = get_test_read_fd();
+
+	pkey_write_deny(pkey);
+	ret = read(test_fd, ptr, 100);
+	dprintf1("read ret: %d\n", ret);
+	if (ret < 0 && (DEBUG_LEVEL > 0))
+		perror("verbose read result (OK for this to be bad)");
+	pkey_assert(ret);
+}
+
+void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
+{
+	int pipe_ret, vmsplice_ret;
+	struct iovec iov;
+	int pipe_fds[2];
+
+	pipe_ret = pipe(pipe_fds);
+
+	pkey_assert(pipe_ret == 0);
+	dprintf1("disabling access to PKEY[%02d], "
+		 "having kernel vmsplice from buffer\n", pkey);
+	pkey_access_deny(pkey);
+	iov.iov_base = ptr;
+	iov.iov_len = PAGE_SIZE;
+	vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
+	dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
+	pkey_assert(vmsplice_ret == -1);
+
+	close(pipe_fds[0]);
+	close(pipe_fds[1]);
+}
+
+void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
+{
+	int ignored = 0xdada;
+	int futex_ret;
+	int some_int = __LINE__;
+
+	dprintf1("disabling write to PKEY[%02d], "
+		 "doing futex gunk in buffer\n", pkey);
+	*ptr = some_int;
+	pkey_write_deny(pkey);
+	futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
+			&ignored, ignored);
+	if (DEBUG_LEVEL > 0)
+		perror("futex");
+	dprintf1("futex() ret: %d\n", futex_ret);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
+{
+	int err;
+	int i;
+
+	/* Note: 0 is the default pkey, so don't mess with it */
+	for (i = 1; i < NR_PKEYS; i++) {
+		if (pkey == i)
+			continue;
+
+		dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
+		err = sys_pkey_free(i);
+		pkey_assert(err);
+
+		err = sys_pkey_free(i);
+		pkey_assert(err);
+
+		err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
+		pkey_assert(err);
+	}
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
+{
+	int err;
+	int bad_pkey = NR_PKEYS+99;
+
+	/* pass a known-invalid pkey in: */
+	err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
+	pkey_assert(err);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
+{
+	int err;
+	int allocated_pkeys[NR_PKEYS] = {0};
+	int nr_allocated_pkeys = 0;
+	int i;
+
+	for (i = 0; i < NR_PKEYS*2; i++) {
+		int new_pkey;
+		dprintf1("%s() alloc loop: %d\n", __func__, i);
+		new_pkey = alloc_pkey();
+		dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+				__LINE__, err, __rdpkru(), shadow_pkru);
+		rdpkru(); /* for shadow checking */
+		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
+		if ((new_pkey == -1) && (errno == ENOSPC)) {
+			dprintf2("%s() failed to allocate pkey after %d tries\n",
+				__func__, nr_allocated_pkeys);
+			break;
+		}
+		pkey_assert(nr_allocated_pkeys < NR_PKEYS);
+		allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
+	}
+
+	dprintf3("%s()::%d\n", __func__, __LINE__);
+
+	/*
+	 * ensure it did not reach the end of the loop without
+	 * failure:
+	 */
+	pkey_assert(i < NR_PKEYS*2);
+
+	/*
+	 * There are 16 pkeys supported in hardware.  One is taken
+	 * up for the default (0) and another can be taken up by
+	 * an execute-only mapping.  Ensure that we can allocate
+	 * at least 14 (16-2).
+	 */
+	pkey_assert(i >= NR_PKEYS-2);
+
+	for (i = 0; i < nr_allocated_pkeys; i++) {
+		err = sys_pkey_free(allocated_pkeys[i]);
+		pkey_assert(!err);
+		rdpkru(); /* for shadow checking */
+	}
+}
+
+void test_ptrace_of_child(int *ptr, u16 pkey)
+{
+	__attribute__((__unused__)) int peek_result;
+	pid_t child_pid;
+	void *ignored = 0;
+	long ret;
+	int status;
+	/*
+	 * This is the "control" for our little expermient.  Make sure
+	 * we can always access it when ptracing.
+	 */
+	int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
+	int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
+
+	/*
+	 * Fork a child which is an exact copy of this process, of course.
+	 * That means we can do all of our tests via ptrace() and then plain
+	 * memory access and ensure they work differently.
+	 */
+	child_pid = fork_lazy_child();
+	dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
+
+	ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
+	if (ret)
+		perror("attach");
+	dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
+	pkey_assert(ret != -1);
+	ret = waitpid(child_pid, &status, WUNTRACED);
+	if ((ret != child_pid) || !(WIFSTOPPED(status))) {
+		fprintf(stderr, "weird waitpid result %ld stat %x\n",
+				ret, status);
+		pkey_assert(0);
+	}
+	dprintf2("waitpid ret: %ld\n", ret);
+	dprintf2("waitpid status: %d\n", status);
+
+	pkey_access_deny(pkey);
+	pkey_write_deny(pkey);
+
+	/* Write access, untested for now:
+	ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
+	pkey_assert(ret != -1);
+	dprintf1("poke at %p: %ld\n", peek_at, ret);
+	*/
+
+	/*
+	 * Try to access the pkey-protected "ptr" via ptrace:
+	 */
+	ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
+	/* expect it to work, without an error: */
+	pkey_assert(ret != -1);
+	/* Now access from the current task, and expect an exception: */
+	peek_result = read_ptr(ptr);
+	expected_pk_fault(pkey);
+
+	/*
+	 * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
+	 */
+	ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
+	/* expect it to work, without an error: */
+	pkey_assert(ret != -1);
+	/* Now access from the current task, and expect NO exception: */
+	peek_result = read_ptr(plain_ptr);
+	do_not_expect_pk_fault();
+
+	ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
+	pkey_assert(ret != -1);
+
+	ret = kill(child_pid, SIGKILL);
+	pkey_assert(ret != -1);
+
+	wait(&status);
+
+	free(plain_ptr_unaligned);
+}
+
+void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
+{
+	void *p1;
+	int scratch;
+	int ptr_contents;
+	int ret;
+
+	p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
+	dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
+	/* lots_o_noops_around_write should be page-aligned already */
+	assert(p1 == &lots_o_noops_around_write);
+
+	/* Point 'p1' at the *second* page of the function: */
+	p1 += PAGE_SIZE;
+
+	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+	lots_o_noops_around_write(&scratch);
+	ptr_contents = read_ptr(p1);
+	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+
+	ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
+	pkey_assert(!ret);
+	pkey_access_deny(pkey);
+
+	dprintf2("pkru: %x\n", rdpkru());
+
+	/*
+	 * Make sure this is an *instruction* fault
+	 */
+	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+	lots_o_noops_around_write(&scratch);
+	do_not_expect_pk_fault();
+	ptr_contents = read_ptr(p1);
+	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+	expected_pk_fault(pkey);
+}
+
+void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
+{
+	int size = PAGE_SIZE;
+	int sret;
+
+	if (cpu_has_pku()) {
+		dprintf1("SKIP: %s: no CPU support\n", __func__);
+		return;
+	}
+
+	sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
+	pkey_assert(sret < 0);
+}
+
+void (*pkey_tests[])(int *ptr, u16 pkey) = {
+	test_read_of_write_disabled_region,
+	test_read_of_access_disabled_region,
+	test_write_of_write_disabled_region,
+	test_write_of_access_disabled_region,
+	test_kernel_write_of_access_disabled_region,
+	test_kernel_write_of_write_disabled_region,
+	test_kernel_gup_of_access_disabled_region,
+	test_kernel_gup_write_to_write_disabled_region,
+	test_executing_on_unreadable_memory,
+	test_ptrace_of_child,
+	test_pkey_syscalls_on_non_allocated_pkey,
+	test_pkey_syscalls_bad_args,
+	test_pkey_alloc_exhaust,
+};
+
+void run_tests_once(void)
+{
+	int *ptr;
+	int prot = PROT_READ|PROT_WRITE;
+
+	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
+		int pkey;
+		int orig_pkru_faults = pkru_faults;
+
+		dprintf1("======================\n");
+		dprintf1("test %d preparing...\n", test_nr);
+
+		tracing_on();
+		pkey = alloc_random_pkey();
+		dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
+		ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
+		dprintf1("test %d starting...\n", test_nr);
+		pkey_tests[test_nr](ptr, pkey);
+		dprintf1("freeing test memory: %p\n", ptr);
+		free_pkey_malloc(ptr);
+		sys_pkey_free(pkey);
+
+		dprintf1("pkru_faults: %d\n", pkru_faults);
+		dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
+
+		tracing_off();
+		close_test_fds();
+
+		printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
+		dprintf1("======================\n\n");
+	}
+	iteration_nr++;
+}
+
+void pkey_setup_shadow(void)
+{
+	shadow_pkru = __rdpkru();
+}
+
+int main(void)
+{
+	int nr_iterations = 22;
+
+	setup_handlers();
+
+	printf("has pku: %d\n", cpu_has_pku());
+
+	if (!cpu_has_pku()) {
+		int size = PAGE_SIZE;
+		int *ptr;
+
+		printf("running PKEY tests for unsupported CPU/OS\n");
+
+		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+		assert(ptr != (void *)-1);
+		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
+		exit(0);
+	}
+
+	pkey_setup_shadow();
+	printf("startup pkru: %x\n", rdpkru());
+	setup_hugetlbfs();
+
+	while (nr_iterations-- > 0)
+		run_tests_once();
+
+	printf("done (all tests OK)\n");
+	return 0;
+}
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile
index 97f187e..fee6181 100644
--- a/tools/testing/selftests/x86/Makefile
+++ b/tools/testing/selftests/x86/Makefile
@@ -6,7 +6,7 @@ include ../lib.mk
 
 TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall test_mremap_vdso \
 			check_initial_reg_state sigreturn ldt_gdt iopl mpx-mini-test ioperm \
-			protection_keys test_vdso
+			test_vdso
 TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault test_syscall_vdso unwind_vdso \
 			test_FCMOV test_FCOMI test_FISTTP \
 			vdso_restorer
diff --git a/tools/testing/selftests/x86/pkey-helpers.h b/tools/testing/selftests/x86/pkey-helpers.h
deleted file mode 100644
index b202939..0000000
--- a/tools/testing/selftests/x86/pkey-helpers.h
+++ /dev/null
@@ -1,219 +0,0 @@
-#ifndef _PKEYS_HELPER_H
-#define _PKEYS_HELPER_H
-#define _GNU_SOURCE
-#include <string.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <signal.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <ucontext.h>
-#include <sys/mman.h>
-
-#define NR_PKEYS 16
-#define PKRU_BITS_PER_PKEY 2
-
-#ifndef DEBUG_LEVEL
-#define DEBUG_LEVEL 0
-#endif
-#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
-extern int dprint_in_signal;
-extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
-static inline void sigsafe_printf(const char *format, ...)
-{
-	va_list ap;
-
-	va_start(ap, format);
-	if (!dprint_in_signal) {
-		vprintf(format, ap);
-	} else {
-		int len = vsnprintf(dprint_in_signal_buffer,
-				    DPRINT_IN_SIGNAL_BUF_SIZE,
-				    format, ap);
-		/*
-		 * len is amount that would have been printed,
-		 * but actual write is truncated at BUF_SIZE.
-		 */
-		if (len > DPRINT_IN_SIGNAL_BUF_SIZE)
-			len = DPRINT_IN_SIGNAL_BUF_SIZE;
-		write(1, dprint_in_signal_buffer, len);
-	}
-	va_end(ap);
-}
-#define dprintf_level(level, args...) do {	\
-	if (level <= DEBUG_LEVEL)		\
-		sigsafe_printf(args);		\
-	fflush(NULL);				\
-} while (0)
-#define dprintf0(args...) dprintf_level(0, args)
-#define dprintf1(args...) dprintf_level(1, args)
-#define dprintf2(args...) dprintf_level(2, args)
-#define dprintf3(args...) dprintf_level(3, args)
-#define dprintf4(args...) dprintf_level(4, args)
-
-extern unsigned int shadow_pkru;
-static inline unsigned int __rdpkru(void)
-{
-	unsigned int eax, edx;
-	unsigned int ecx = 0;
-	unsigned int pkru;
-
-	asm volatile(".byte 0x0f,0x01,0xee\n\t"
-		     : "=a" (eax), "=d" (edx)
-		     : "c" (ecx));
-	pkru = eax;
-	return pkru;
-}
-
-static inline unsigned int _rdpkru(int line)
-{
-	unsigned int pkru = __rdpkru();
-
-	dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
-			line, pkru, shadow_pkru);
-	assert(pkru == shadow_pkru);
-
-	return pkru;
-}
-
-#define rdpkru() _rdpkru(__LINE__)
-
-static inline void __wrpkru(unsigned int pkru)
-{
-	unsigned int eax = pkru;
-	unsigned int ecx = 0;
-	unsigned int edx = 0;
-
-	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
-	asm volatile(".byte 0x0f,0x01,0xef\n\t"
-		     : : "a" (eax), "c" (ecx), "d" (edx));
-	assert(pkru == __rdpkru());
-}
-
-static inline void wrpkru(unsigned int pkru)
-{
-	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
-	/* will do the shadow check for us: */
-	rdpkru();
-	__wrpkru(pkru);
-	shadow_pkru = pkru;
-	dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
-}
-
-/*
- * These are technically racy. since something could
- * change PKRU between the read and the write.
- */
-static inline void __pkey_access_allow(int pkey, int do_allow)
-{
-	unsigned int pkru = rdpkru();
-	int bit = pkey * 2;
-
-	if (do_allow)
-		pkru &= (1<<bit);
-	else
-		pkru |= (1<<bit);
-
-	dprintf4("pkru now: %08x\n", rdpkru());
-	wrpkru(pkru);
-}
-
-static inline void __pkey_write_allow(int pkey, int do_allow_write)
-{
-	long pkru = rdpkru();
-	int bit = pkey * 2 + 1;
-
-	if (do_allow_write)
-		pkru &= (1<<bit);
-	else
-		pkru |= (1<<bit);
-
-	wrpkru(pkru);
-	dprintf4("pkru now: %08x\n", rdpkru());
-}
-
-#define PROT_PKEY0     0x10            /* protection key value (bit 0) */
-#define PROT_PKEY1     0x20            /* protection key value (bit 1) */
-#define PROT_PKEY2     0x40            /* protection key value (bit 2) */
-#define PROT_PKEY3     0x80            /* protection key value (bit 3) */
-
-#define PAGE_SIZE 4096
-#define MB	(1<<20)
-
-static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
-		unsigned int *ecx, unsigned int *edx)
-{
-	/* ecx is often an input as well as an output. */
-	asm volatile(
-		"cpuid;"
-		: "=a" (*eax),
-		  "=b" (*ebx),
-		  "=c" (*ecx),
-		  "=d" (*edx)
-		: "0" (*eax), "2" (*ecx));
-}
-
-/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
-#define X86_FEATURE_PKU        (1<<3) /* Protection Keys for Userspace */
-#define X86_FEATURE_OSPKE      (1<<4) /* OS Protection Keys Enable */
-
-static inline int cpu_has_pku(void)
-{
-	unsigned int eax;
-	unsigned int ebx;
-	unsigned int ecx;
-	unsigned int edx;
-
-	eax = 0x7;
-	ecx = 0x0;
-	__cpuid(&eax, &ebx, &ecx, &edx);
-
-	if (!(ecx & X86_FEATURE_PKU)) {
-		dprintf2("cpu does not have PKU\n");
-		return 0;
-	}
-	if (!(ecx & X86_FEATURE_OSPKE)) {
-		dprintf2("cpu does not have OSPKE\n");
-		return 0;
-	}
-	return 1;
-}
-
-#define XSTATE_PKRU_BIT	(9)
-#define XSTATE_PKRU	0x200
-
-int pkru_xstate_offset(void)
-{
-	unsigned int eax;
-	unsigned int ebx;
-	unsigned int ecx;
-	unsigned int edx;
-	int xstate_offset;
-	int xstate_size;
-	unsigned long XSTATE_CPUID = 0xd;
-	int leaf;
-
-	/* assume that XSTATE_PKRU is set in XCR0 */
-	leaf = XSTATE_PKRU_BIT;
-	{
-		eax = XSTATE_CPUID;
-		ecx = leaf;
-		__cpuid(&eax, &ebx, &ecx, &edx);
-
-		if (leaf == XSTATE_PKRU_BIT) {
-			xstate_offset = ebx;
-			xstate_size = eax;
-		}
-	}
-
-	if (xstate_size == 0) {
-		printf("could not find size/offset of PKRU in xsave state\n");
-		return 0;
-	}
-
-	return xstate_offset;
-}
-
-#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c
deleted file mode 100644
index 3237bc0..0000000
--- a/tools/testing/selftests/x86/protection_keys.c
+++ /dev/null
@@ -1,1395 +0,0 @@
-/*
- * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
- *
- * There are examples in here of:
- *  * how to set protection keys on memory
- *  * how to set/clear bits in PKRU (the rights register)
- *  * how to handle SEGV_PKRU signals and extract pkey-relevant
- *    information from the siginfo
- *
- * Things to add:
- *	make sure KSM and KSM COW breaking works
- *	prefault pages in at malloc, or not
- *	protect MPX bounds tables with protection keys?
- *	make sure VMA splitting/merging is working correctly
- *	OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
- *	look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
- *	do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
- *
- * Compile like this:
- *	gcc      -o protection_keys    -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- *	gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- */
-#define _GNU_SOURCE
-#include <errno.h>
-#include <linux/futex.h>
-#include <sys/time.h>
-#include <sys/syscall.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <signal.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <ucontext.h>
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <sys/ptrace.h>
-#include <setjmp.h>
-
-#include "pkey-helpers.h"
-
-int iteration_nr = 1;
-int test_nr;
-
-unsigned int shadow_pkru;
-
-#define HPAGE_SIZE	(1UL<<21)
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
-#define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
-#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
-#define ALIGN_PTR_UP(p, ptr_align_to)	((typeof(p))ALIGN_UP((unsigned long)(p),	ptr_align_to))
-#define ALIGN_PTR_DOWN(p, ptr_align_to)	((typeof(p))ALIGN_DOWN((unsigned long)(p),	ptr_align_to))
-#define __stringify_1(x...)     #x
-#define __stringify(x...)       __stringify_1(x)
-
-#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
-
-int dprint_in_signal;
-char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
-
-extern void abort_hooks(void);
-#define pkey_assert(condition) do {		\
-	if (!(condition)) {			\
-		dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
-				__FILE__, __LINE__,	\
-				test_nr, iteration_nr);	\
-		dprintf0("errno at assert: %d", errno);	\
-		abort_hooks();			\
-		assert(condition);		\
-	}					\
-} while (0)
-#define raw_assert(cond) assert(cond)
-
-void cat_into_file(char *str, char *file)
-{
-	int fd = open(file, O_RDWR);
-	int ret;
-
-	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
-	/*
-	 * these need to be raw because they are called under
-	 * pkey_assert()
-	 */
-	raw_assert(fd >= 0);
-	ret = write(fd, str, strlen(str));
-	if (ret != strlen(str)) {
-		perror("write to file failed");
-		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
-		raw_assert(0);
-	}
-	close(fd);
-}
-
-#if CONTROL_TRACING > 0
-static int warned_tracing;
-int tracing_root_ok(void)
-{
-	if (geteuid() != 0) {
-		if (!warned_tracing)
-			fprintf(stderr, "WARNING: not run as root, "
-					"can not do tracing control\n");
-		warned_tracing = 1;
-		return 0;
-	}
-	return 1;
-}
-#endif
-
-void tracing_on(void)
-{
-#if CONTROL_TRACING > 0
-#define TRACEDIR "/sys/kernel/debug/tracing"
-	char pidstr[32];
-
-	if (!tracing_root_ok())
-		return;
-
-	sprintf(pidstr, "%d", getpid());
-	cat_into_file("0", TRACEDIR "/tracing_on");
-	cat_into_file("\n", TRACEDIR "/trace");
-	if (1) {
-		cat_into_file("function_graph", TRACEDIR "/current_tracer");
-		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
-	} else {
-		cat_into_file("nop", TRACEDIR "/current_tracer");
-	}
-	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
-	cat_into_file("1", TRACEDIR "/tracing_on");
-	dprintf1("enabled tracing\n");
-#endif
-}
-
-void tracing_off(void)
-{
-#if CONTROL_TRACING > 0
-	if (!tracing_root_ok())
-		return;
-	cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
-#endif
-}
-
-void abort_hooks(void)
-{
-	fprintf(stderr, "running %s()...\n", __func__);
-	tracing_off();
-#ifdef SLEEP_ON_ABORT
-	sleep(SLEEP_ON_ABORT);
-#endif
-}
-
-static inline void __page_o_noops(void)
-{
-	/* 8-bytes of instruction * 512 bytes = 1 page */
-	asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
-}
-
-/*
- * This attempts to have roughly a page of instructions followed by a few
- * instructions that do a write, and another page of instructions.  That
- * way, we are pretty sure that the write is in the second page of
- * instructions and has at least a page of padding behind it.
- *
- * *That* lets us be sure to madvise() away the write instruction, which
- * will then fault, which makes sure that the fault code handles
- * execute-only memory properly.
- */
-__attribute__((__aligned__(PAGE_SIZE)))
-void lots_o_noops_around_write(int *write_to_me)
-{
-	dprintf3("running %s()\n", __func__);
-	__page_o_noops();
-	/* Assume this happens in the second page of instructions: */
-	*write_to_me = __LINE__;
-	/* pad out by another page: */
-	__page_o_noops();
-	dprintf3("%s() done\n", __func__);
-}
-
-/* Define some kernel-like types */
-#define  u8 uint8_t
-#define u16 uint16_t
-#define u32 uint32_t
-#define u64 uint64_t
-
-#ifdef __i386__
-#define SYS_mprotect_key 380
-#define SYS_pkey_alloc	 381
-#define SYS_pkey_free	 382
-#define REG_IP_IDX REG_EIP
-#define si_pkey_offset 0x14
-#else
-#define SYS_mprotect_key 329
-#define SYS_pkey_alloc	 330
-#define SYS_pkey_free	 331
-#define REG_IP_IDX REG_RIP
-#define si_pkey_offset 0x20
-#endif
-
-void dump_mem(void *dumpme, int len_bytes)
-{
-	char *c = (void *)dumpme;
-	int i;
-
-	for (i = 0; i < len_bytes; i += sizeof(u64)) {
-		u64 *ptr = (u64 *)(c + i);
-		dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
-	}
-}
-
-#define __SI_FAULT      (3 << 16)
-#define SEGV_BNDERR     (__SI_FAULT|3)  /* failed address bound checks */
-#define SEGV_PKUERR     (__SI_FAULT|4)
-
-static char *si_code_str(int si_code)
-{
-	if (si_code & SEGV_MAPERR)
-		return "SEGV_MAPERR";
-	if (si_code & SEGV_ACCERR)
-		return "SEGV_ACCERR";
-	if (si_code & SEGV_BNDERR)
-		return "SEGV_BNDERR";
-	if (si_code & SEGV_PKUERR)
-		return "SEGV_PKUERR";
-	return "UNKNOWN";
-}
-
-int pkru_faults;
-int last_si_pkey = -1;
-void signal_handler(int signum, siginfo_t *si, void *vucontext)
-{
-	ucontext_t *uctxt = vucontext;
-	int trapno;
-	unsigned long ip;
-	char *fpregs;
-	u32 *pkru_ptr;
-	u64 si_pkey;
-	u32 *si_pkey_ptr;
-	int pkru_offset;
-	fpregset_t fpregset;
-
-	dprint_in_signal = 1;
-	dprintf1(">>>>===============SIGSEGV============================\n");
-	dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
-			__rdpkru(), shadow_pkru);
-
-	trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
-	ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
-	fpregset = uctxt->uc_mcontext.fpregs;
-	fpregs = (void *)fpregset;
-
-	dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
-			trapno, ip, si_code_str(si->si_code), si->si_code);
-#ifdef __i386__
-	/*
-	 * 32-bit has some extra padding so that userspace can tell whether
-	 * the XSTATE header is present in addition to the "legacy" FPU
-	 * state.  We just assume that it is here.
-	 */
-	fpregs += 0x70;
-#endif
-	pkru_offset = pkru_xstate_offset();
-	pkru_ptr = (void *)(&fpregs[pkru_offset]);
-
-	dprintf1("siginfo: %p\n", si);
-	dprintf1(" fpregs: %p\n", fpregs);
-	/*
-	 * If we got a PKRU fault, we *HAVE* to have at least one bit set in
-	 * here.
-	 */
-	dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
-	if (DEBUG_LEVEL > 4)
-		dump_mem(pkru_ptr - 128, 256);
-	pkey_assert(*pkru_ptr);
-
-	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
-	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
-	dump_mem(si_pkey_ptr - 8, 24);
-	si_pkey = *si_pkey_ptr;
-	pkey_assert(si_pkey < NR_PKEYS);
-	last_si_pkey = si_pkey;
-
-	if ((si->si_code == SEGV_MAPERR) ||
-	    (si->si_code == SEGV_ACCERR) ||
-	    (si->si_code == SEGV_BNDERR)) {
-		printf("non-PK si_code, exiting...\n");
-		exit(4);
-	}
-
-	dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
-	/* need __rdpkru() version so we do not do shadow_pkru checking */
-	dprintf1("signal pkru from  pkru: %08x\n", __rdpkru());
-	dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
-	*(u64 *)pkru_ptr = 0x00000000;
-	dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
-	pkru_faults++;
-	dprintf1("<<<<==================================================\n");
-	return;
-	if (trapno == 14) {
-		fprintf(stderr,
-			"ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
-			trapno, ip);
-		fprintf(stderr, "si_addr %p\n", si->si_addr);
-		fprintf(stderr, "REG_ERR: %lx\n",
-				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
-		exit(1);
-	} else {
-		fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
-		fprintf(stderr, "si_addr %p\n", si->si_addr);
-		fprintf(stderr, "REG_ERR: %lx\n",
-				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
-		exit(2);
-	}
-	dprint_in_signal = 0;
-}
-
-int wait_all_children(void)
-{
-	int status;
-	return waitpid(-1, &status, 0);
-}
-
-void sig_chld(int x)
-{
-	dprint_in_signal = 1;
-	dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
-	dprint_in_signal = 0;
-}
-
-void setup_sigsegv_handler(void)
-{
-	int r, rs;
-	struct sigaction newact;
-	struct sigaction oldact;
-
-	/* #PF is mapped to sigsegv */
-	int signum  = SIGSEGV;
-
-	newact.sa_handler = 0;
-	newact.sa_sigaction = signal_handler;
-
-	/*sigset_t - signals to block while in the handler */
-	/* get the old signal mask. */
-	rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
-	pkey_assert(rs == 0);
-
-	/* call sa_sigaction, not sa_handler*/
-	newact.sa_flags = SA_SIGINFO;
-
-	newact.sa_restorer = 0;  /* void(*)(), obsolete */
-	r = sigaction(signum, &newact, &oldact);
-	r = sigaction(SIGALRM, &newact, &oldact);
-	pkey_assert(r == 0);
-}
-
-void setup_handlers(void)
-{
-	signal(SIGCHLD, &sig_chld);
-	setup_sigsegv_handler();
-}
-
-pid_t fork_lazy_child(void)
-{
-	pid_t forkret;
-
-	forkret = fork();
-	pkey_assert(forkret >= 0);
-	dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
-
-	if (!forkret) {
-		/* in the child */
-		while (1) {
-			dprintf1("child sleeping...\n");
-			sleep(30);
-		}
-	}
-	return forkret;
-}
-
-void davecmp(void *_a, void *_b, int len)
-{
-	int i;
-	unsigned long *a = _a;
-	unsigned long *b = _b;
-
-	for (i = 0; i < len / sizeof(*a); i++) {
-		if (a[i] == b[i])
-			continue;
-
-		dprintf3("[%3d]: a: %016lx b: %016lx\n", i, a[i], b[i]);
-	}
-}
-
-void dumpit(char *f)
-{
-	int fd = open(f, O_RDONLY);
-	char buf[100];
-	int nr_read;
-
-	dprintf2("maps fd: %d\n", fd);
-	do {
-		nr_read = read(fd, &buf[0], sizeof(buf));
-		write(1, buf, nr_read);
-	} while (nr_read > 0);
-	close(fd);
-}
-
-#define PKEY_DISABLE_ACCESS    0x1
-#define PKEY_DISABLE_WRITE     0x2
-
-u32 pkey_get(int pkey, unsigned long flags)
-{
-	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
-	u32 pkru = __rdpkru();
-	u32 shifted_pkru;
-	u32 masked_pkru;
-
-	dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
-			__func__, pkey, flags, 0, 0);
-	dprintf2("%s() raw pkru: %x\n", __func__, pkru);
-
-	shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
-	dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
-	masked_pkru = shifted_pkru & mask;
-	dprintf2("%s() masked  pkru: %x\n", __func__, masked_pkru);
-	/*
-	 * shift down the relevant bits to the lowest two, then
-	 * mask off all the other high bits.
-	 */
-	return masked_pkru;
-}
-
-int pkey_set(int pkey, unsigned long rights, unsigned long flags)
-{
-	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
-	u32 old_pkru = __rdpkru();
-	u32 new_pkru;
-
-	/* make sure that 'rights' only contains the bits we expect: */
-	assert(!(rights & ~mask));
-
-	/* copy old pkru */
-	new_pkru = old_pkru;
-	/* mask out bits from pkey in old value: */
-	new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
-	/* OR in new bits for pkey: */
-	new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
-
-	__wrpkru(new_pkru);
-
-	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
-			__func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
-	return 0;
-}
-
-void pkey_disable_set(int pkey, int flags)
-{
-	unsigned long syscall_flags = 0;
-	int ret;
-	int pkey_rights;
-	u32 orig_pkru = rdpkru();
-
-	dprintf1("START->%s(%d, 0x%x)\n", __func__,
-		pkey, flags);
-	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
-
-	pkey_rights = pkey_get(pkey, syscall_flags);
-
-	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
-			pkey, pkey, pkey_rights);
-	pkey_assert(pkey_rights >= 0);
-
-	pkey_rights |= flags;
-
-	ret = pkey_set(pkey, pkey_rights, syscall_flags);
-	assert(!ret);
-	/*pkru and flags have the same format */
-	shadow_pkru |= flags << (pkey * 2);
-	dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
-
-	pkey_assert(ret >= 0);
-
-	pkey_rights = pkey_get(pkey, syscall_flags);
-	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
-			pkey, pkey, pkey_rights);
-
-	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
-	if (flags)
-		pkey_assert(rdpkru() > orig_pkru);
-	dprintf1("END<---%s(%d, 0x%x)\n", __func__,
-		pkey, flags);
-}
-
-void pkey_disable_clear(int pkey, int flags)
-{
-	unsigned long syscall_flags = 0;
-	int ret;
-	int pkey_rights = pkey_get(pkey, syscall_flags);
-	u32 orig_pkru = rdpkru();
-
-	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
-
-	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
-			pkey, pkey, pkey_rights);
-	pkey_assert(pkey_rights >= 0);
-
-	pkey_rights |= flags;
-
-	ret = pkey_set(pkey, pkey_rights, 0);
-	/* pkru and flags have the same format */
-	shadow_pkru &= ~(flags << (pkey * 2));
-	pkey_assert(ret >= 0);
-
-	pkey_rights = pkey_get(pkey, syscall_flags);
-	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
-			pkey, pkey, pkey_rights);
-
-	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
-	if (flags)
-		assert(rdpkru() > orig_pkru);
-}
-
-void pkey_write_allow(int pkey)
-{
-	pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
-}
-void pkey_write_deny(int pkey)
-{
-	pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
-}
-void pkey_access_allow(int pkey)
-{
-	pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
-}
-void pkey_access_deny(int pkey)
-{
-	pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
-}
-
-int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
-		unsigned long pkey)
-{
-	int sret;
-
-	dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
-			ptr, size, orig_prot, pkey);
-
-	errno = 0;
-	sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
-	if (errno) {
-		dprintf2("SYS_mprotect_key sret: %d\n", sret);
-		dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
-		dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
-		if (DEBUG_LEVEL >= 2)
-			perror("SYS_mprotect_pkey");
-	}
-	return sret;
-}
-
-int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
-{
-	int ret = syscall(SYS_pkey_alloc, flags, init_val);
-	dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
-			__func__, flags, init_val, ret, errno);
-	return ret;
-}
-
-int alloc_pkey(void)
-{
-	int ret;
-	unsigned long init_val = 0x0;
-
-	dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
-			__LINE__, __rdpkru(), shadow_pkru);
-	ret = sys_pkey_alloc(0, init_val);
-	/*
-	 * pkey_alloc() sets PKRU, so we need to reflect it in
-	 * shadow_pkru:
-	 */
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	if (ret) {
-		/* clear both the bits: */
-		shadow_pkru &= ~(0x3      << (ret * 2));
-		dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-				__LINE__, ret, __rdpkru(), shadow_pkru);
-		/*
-		 * move the new state in from init_val
-		 * (remember, we cheated and init_val == pkru format)
-		 */
-		shadow_pkru |=  (init_val << (ret * 2));
-	}
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
-	/* for shadow checking: */
-	rdpkru();
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	return ret;
-}
-
-int sys_pkey_free(unsigned long pkey)
-{
-	int ret = syscall(SYS_pkey_free, pkey);
-	dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
-	return ret;
-}
-
-/*
- * I had a bug where pkey bits could be set by mprotect() but
- * not cleared.  This ensures we get lots of random bit sets
- * and clears on the vma and pte pkey bits.
- */
-int alloc_random_pkey(void)
-{
-	int max_nr_pkey_allocs;
-	int ret;
-	int i;
-	int alloced_pkeys[NR_PKEYS];
-	int nr_alloced = 0;
-	int random_index;
-	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
-
-	/* allocate every possible key and make a note of which ones we got */
-	max_nr_pkey_allocs = NR_PKEYS;
-	max_nr_pkey_allocs = 1;
-	for (i = 0; i < max_nr_pkey_allocs; i++) {
-		int new_pkey = alloc_pkey();
-		if (new_pkey < 0)
-			break;
-		alloced_pkeys[nr_alloced++] = new_pkey;
-	}
-
-	pkey_assert(nr_alloced > 0);
-	/* select a random one out of the allocated ones */
-	random_index = rand() % nr_alloced;
-	ret = alloced_pkeys[random_index];
-	/* now zero it out so we don't free it next */
-	alloced_pkeys[random_index] = 0;
-
-	/* go through the allocated ones that we did not want and free them */
-	for (i = 0; i < nr_alloced; i++) {
-		int free_ret;
-		if (!alloced_pkeys[i])
-			continue;
-		free_ret = sys_pkey_free(alloced_pkeys[i]);
-		pkey_assert(!free_ret);
-	}
-	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	return ret;
-}
-
-int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
-		unsigned long pkey)
-{
-	int nr_iterations = random() % 100;
-	int ret;
-
-	while (0) {
-		int rpkey = alloc_random_pkey();
-		ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
-		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
-				ptr, size, orig_prot, pkey, ret);
-		if (nr_iterations-- < 0)
-			break;
-
-		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-		sys_pkey_free(rpkey);
-		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	}
-	pkey_assert(pkey < NR_PKEYS);
-
-	ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
-	dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
-			ptr, size, orig_prot, pkey, ret);
-	pkey_assert(!ret);
-	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	return ret;
-}
-
-struct pkey_malloc_record {
-	void *ptr;
-	long size;
-};
-struct pkey_malloc_record *pkey_malloc_records;
-long nr_pkey_malloc_records;
-void record_pkey_malloc(void *ptr, long size)
-{
-	long i;
-	struct pkey_malloc_record *rec = NULL;
-
-	for (i = 0; i < nr_pkey_malloc_records; i++) {
-		rec = &pkey_malloc_records[i];
-		/* find a free record */
-		if (rec)
-			break;
-	}
-	if (!rec) {
-		/* every record is full */
-		size_t old_nr_records = nr_pkey_malloc_records;
-		size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
-		size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
-		dprintf2("new_nr_records: %zd\n", new_nr_records);
-		dprintf2("new_size: %zd\n", new_size);
-		pkey_malloc_records = realloc(pkey_malloc_records, new_size);
-		pkey_assert(pkey_malloc_records != NULL);
-		rec = &pkey_malloc_records[nr_pkey_malloc_records];
-		/*
-		 * realloc() does not initialize memory, so zero it from
-		 * the first new record all the way to the end.
-		 */
-		for (i = 0; i < new_nr_records - old_nr_records; i++)
-			memset(rec + i, 0, sizeof(*rec));
-	}
-	dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
-		(int)(rec - pkey_malloc_records), rec, ptr, size);
-	rec->ptr = ptr;
-	rec->size = size;
-	nr_pkey_malloc_records++;
-}
-
-void free_pkey_malloc(void *ptr)
-{
-	long i;
-	int ret;
-	dprintf3("%s(%p)\n", __func__, ptr);
-	for (i = 0; i < nr_pkey_malloc_records; i++) {
-		struct pkey_malloc_record *rec = &pkey_malloc_records[i];
-		dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
-				ptr, i, rec, rec->ptr, rec->size);
-		if ((ptr <  rec->ptr) ||
-		    (ptr >= rec->ptr + rec->size))
-			continue;
-
-		dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
-				ptr, i, rec, rec->ptr, rec->size);
-		nr_pkey_malloc_records--;
-		ret = munmap(rec->ptr, rec->size);
-		dprintf3("munmap ret: %d\n", ret);
-		pkey_assert(!ret);
-		dprintf3("clearing rec->ptr, rec: %p\n", rec);
-		rec->ptr = NULL;
-		dprintf3("done clearing rec->ptr, rec: %p\n", rec);
-		return;
-	}
-	pkey_assert(false);
-}
-
-
-void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
-{
-	void *ptr;
-	int ret;
-
-	rdpkru();
-	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
-			size, prot, pkey);
-	pkey_assert(pkey < NR_PKEYS);
-	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	pkey_assert(ptr != (void *)-1);
-	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
-	pkey_assert(!ret);
-	record_pkey_malloc(ptr, size);
-	rdpkru();
-
-	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
-	return ptr;
-}
-
-void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
-{
-	int ret;
-	void *ptr;
-
-	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
-			size, prot, pkey);
-	/*
-	 * Guarantee we can fit at least one huge page in the resulting
-	 * allocation by allocating space for 2:
-	 */
-	size = ALIGN_UP(size, HPAGE_SIZE * 2);
-	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	pkey_assert(ptr != (void *)-1);
-	record_pkey_malloc(ptr, size);
-	mprotect_pkey(ptr, size, prot, pkey);
-
-	dprintf1("unaligned ptr: %p\n", ptr);
-	ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
-	dprintf1("  aligned ptr: %p\n", ptr);
-	ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
-	dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
-	ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
-	dprintf1("MADV_WILLNEED ret: %d\n", ret);
-	memset(ptr, 0, HPAGE_SIZE);
-
-	dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
-	return ptr;
-}
-
-int hugetlb_setup_ok;
-#define GET_NR_HUGE_PAGES 10
-void setup_hugetlbfs(void)
-{
-	int err;
-	int fd;
-	char buf[] = "123";
-
-	if (geteuid() != 0) {
-		fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
-		return;
-	}
-
-	cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
-
-	/*
-	 * Now go make sure that we got the pages and that they
-	 * are 2M pages.  Someone might have made 1G the default.
-	 */
-	fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
-	if (fd < 0) {
-		perror("opening sysfs 2M hugetlb config");
-		return;
-	}
-
-	/* -1 to guarantee leaving the trailing \0 */
-	err = read(fd, buf, sizeof(buf)-1);
-	close(fd);
-	if (err <= 0) {
-		perror("reading sysfs 2M hugetlb config");
-		return;
-	}
-
-	if (atoi(buf) != GET_NR_HUGE_PAGES) {
-		fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
-			buf, GET_NR_HUGE_PAGES);
-		return;
-	}
-
-	hugetlb_setup_ok = 1;
-}
-
-void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
-{
-	void *ptr;
-	int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
-
-	if (!hugetlb_setup_ok)
-		return PTR_ERR_ENOTSUP;
-
-	dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
-	size = ALIGN_UP(size, HPAGE_SIZE * 2);
-	pkey_assert(pkey < NR_PKEYS);
-	ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
-	pkey_assert(ptr != (void *)-1);
-	mprotect_pkey(ptr, size, prot, pkey);
-
-	record_pkey_malloc(ptr, size);
-
-	dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
-	return ptr;
-}
-
-void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
-{
-	void *ptr;
-	int fd;
-
-	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
-			size, prot, pkey);
-	pkey_assert(pkey < NR_PKEYS);
-	fd = open("/dax/foo", O_RDWR);
-	pkey_assert(fd >= 0);
-
-	ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
-	pkey_assert(ptr != (void *)-1);
-
-	mprotect_pkey(ptr, size, prot, pkey);
-
-	record_pkey_malloc(ptr, size);
-
-	dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
-	close(fd);
-	return ptr;
-}
-
-void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
-
-	malloc_pkey_with_mprotect,
-	malloc_pkey_anon_huge,
-	malloc_pkey_hugetlb
-/* can not do direct with the pkey_mprotect() API:
-	malloc_pkey_mmap_direct,
-	malloc_pkey_mmap_dax,
-*/
-};
-
-void *malloc_pkey(long size, int prot, u16 pkey)
-{
-	void *ret;
-	static int malloc_type;
-	int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
-
-	pkey_assert(pkey < NR_PKEYS);
-
-	while (1) {
-		pkey_assert(malloc_type < nr_malloc_types);
-
-		ret = pkey_malloc[malloc_type](size, prot, pkey);
-		pkey_assert(ret != (void *)-1);
-
-		malloc_type++;
-		if (malloc_type >= nr_malloc_types)
-			malloc_type = (random()%nr_malloc_types);
-
-		/* try again if the malloc_type we tried is unsupported */
-		if (ret == PTR_ERR_ENOTSUP)
-			continue;
-
-		break;
-	}
-
-	dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
-			size, prot, pkey, ret);
-	return ret;
-}
-
-int last_pkru_faults;
-void expected_pk_fault(int pkey)
-{
-	dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
-			__func__, last_pkru_faults, pkru_faults);
-	dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
-	pkey_assert(last_pkru_faults + 1 == pkru_faults);
-	pkey_assert(last_si_pkey == pkey);
-	/*
-	 * The signal handler shold have cleared out PKRU to let the
-	 * test program continue.  We now have to restore it.
-	 */
-	if (__rdpkru() != 0)
-		pkey_assert(0);
-
-	__wrpkru(shadow_pkru);
-	dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
-			__func__, shadow_pkru);
-	last_pkru_faults = pkru_faults;
-	last_si_pkey = -1;
-}
-
-void do_not_expect_pk_fault(void)
-{
-	pkey_assert(last_pkru_faults == pkru_faults);
-}
-
-int test_fds[10] = { -1 };
-int nr_test_fds;
-void __save_test_fd(int fd)
-{
-	pkey_assert(fd >= 0);
-	pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
-	test_fds[nr_test_fds] = fd;
-	nr_test_fds++;
-}
-
-int get_test_read_fd(void)
-{
-	int test_fd = open("/etc/passwd", O_RDONLY);
-	__save_test_fd(test_fd);
-	return test_fd;
-}
-
-void close_test_fds(void)
-{
-	int i;
-
-	for (i = 0; i < nr_test_fds; i++) {
-		if (test_fds[i] < 0)
-			continue;
-		close(test_fds[i]);
-		test_fds[i] = -1;
-	}
-	nr_test_fds = 0;
-}
-
-#define barrier() __asm__ __volatile__("": : :"memory")
-__attribute__((noinline)) int read_ptr(int *ptr)
-{
-	/*
-	 * Keep GCC from optimizing this away somehow
-	 */
-	barrier();
-	return *ptr;
-}
-
-void test_read_of_write_disabled_region(int *ptr, u16 pkey)
-{
-	int ptr_contents;
-
-	dprintf1("disabling write access to PKEY[1], doing read\n");
-	pkey_write_deny(pkey);
-	ptr_contents = read_ptr(ptr);
-	dprintf1("*ptr: %d\n", ptr_contents);
-	dprintf1("\n");
-}
-void test_read_of_access_disabled_region(int *ptr, u16 pkey)
-{
-	int ptr_contents;
-
-	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
-	rdpkru();
-	pkey_access_deny(pkey);
-	ptr_contents = read_ptr(ptr);
-	dprintf1("*ptr: %d\n", ptr_contents);
-	expected_pk_fault(pkey);
-}
-void test_write_of_write_disabled_region(int *ptr, u16 pkey)
-{
-	dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
-	pkey_write_deny(pkey);
-	*ptr = __LINE__;
-	expected_pk_fault(pkey);
-}
-void test_write_of_access_disabled_region(int *ptr, u16 pkey)
-{
-	dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
-	pkey_access_deny(pkey);
-	*ptr = __LINE__;
-	expected_pk_fault(pkey);
-}
-void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
-{
-	int ret;
-	int test_fd = get_test_read_fd();
-
-	dprintf1("disabling access to PKEY[%02d], "
-		 "having kernel read() to buffer\n", pkey);
-	pkey_access_deny(pkey);
-	ret = read(test_fd, ptr, 1);
-	dprintf1("read ret: %d\n", ret);
-	pkey_assert(ret);
-}
-void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
-{
-	int ret;
-	int test_fd = get_test_read_fd();
-
-	pkey_write_deny(pkey);
-	ret = read(test_fd, ptr, 100);
-	dprintf1("read ret: %d\n", ret);
-	if (ret < 0 && (DEBUG_LEVEL > 0))
-		perror("verbose read result (OK for this to be bad)");
-	pkey_assert(ret);
-}
-
-void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
-{
-	int pipe_ret, vmsplice_ret;
-	struct iovec iov;
-	int pipe_fds[2];
-
-	pipe_ret = pipe(pipe_fds);
-
-	pkey_assert(pipe_ret == 0);
-	dprintf1("disabling access to PKEY[%02d], "
-		 "having kernel vmsplice from buffer\n", pkey);
-	pkey_access_deny(pkey);
-	iov.iov_base = ptr;
-	iov.iov_len = PAGE_SIZE;
-	vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
-	dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
-	pkey_assert(vmsplice_ret == -1);
-
-	close(pipe_fds[0]);
-	close(pipe_fds[1]);
-}
-
-void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
-{
-	int ignored = 0xdada;
-	int futex_ret;
-	int some_int = __LINE__;
-
-	dprintf1("disabling write to PKEY[%02d], "
-		 "doing futex gunk in buffer\n", pkey);
-	*ptr = some_int;
-	pkey_write_deny(pkey);
-	futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
-			&ignored, ignored);
-	if (DEBUG_LEVEL > 0)
-		perror("futex");
-	dprintf1("futex() ret: %d\n", futex_ret);
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
-{
-	int err;
-	int i;
-
-	/* Note: 0 is the default pkey, so don't mess with it */
-	for (i = 1; i < NR_PKEYS; i++) {
-		if (pkey == i)
-			continue;
-
-		dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
-		err = sys_pkey_free(i);
-		pkey_assert(err);
-
-		err = sys_pkey_free(i);
-		pkey_assert(err);
-
-		err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
-		pkey_assert(err);
-	}
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
-{
-	int err;
-	int bad_pkey = NR_PKEYS+99;
-
-	/* pass a known-invalid pkey in: */
-	err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
-	pkey_assert(err);
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
-{
-	int err;
-	int allocated_pkeys[NR_PKEYS] = {0};
-	int nr_allocated_pkeys = 0;
-	int i;
-
-	for (i = 0; i < NR_PKEYS*2; i++) {
-		int new_pkey;
-		dprintf1("%s() alloc loop: %d\n", __func__, i);
-		new_pkey = alloc_pkey();
-		dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-				__LINE__, err, __rdpkru(), shadow_pkru);
-		rdpkru(); /* for shadow checking */
-		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
-		if ((new_pkey == -1) && (errno == ENOSPC)) {
-			dprintf2("%s() failed to allocate pkey after %d tries\n",
-				__func__, nr_allocated_pkeys);
-			break;
-		}
-		pkey_assert(nr_allocated_pkeys < NR_PKEYS);
-		allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
-	}
-
-	dprintf3("%s()::%d\n", __func__, __LINE__);
-
-	/*
-	 * ensure it did not reach the end of the loop without
-	 * failure:
-	 */
-	pkey_assert(i < NR_PKEYS*2);
-
-	/*
-	 * There are 16 pkeys supported in hardware.  One is taken
-	 * up for the default (0) and another can be taken up by
-	 * an execute-only mapping.  Ensure that we can allocate
-	 * at least 14 (16-2).
-	 */
-	pkey_assert(i >= NR_PKEYS-2);
-
-	for (i = 0; i < nr_allocated_pkeys; i++) {
-		err = sys_pkey_free(allocated_pkeys[i]);
-		pkey_assert(!err);
-		rdpkru(); /* for shadow checking */
-	}
-}
-
-void test_ptrace_of_child(int *ptr, u16 pkey)
-{
-	__attribute__((__unused__)) int peek_result;
-	pid_t child_pid;
-	void *ignored = 0;
-	long ret;
-	int status;
-	/*
-	 * This is the "control" for our little expermient.  Make sure
-	 * we can always access it when ptracing.
-	 */
-	int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
-	int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
-
-	/*
-	 * Fork a child which is an exact copy of this process, of course.
-	 * That means we can do all of our tests via ptrace() and then plain
-	 * memory access and ensure they work differently.
-	 */
-	child_pid = fork_lazy_child();
-	dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
-
-	ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
-	if (ret)
-		perror("attach");
-	dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
-	pkey_assert(ret != -1);
-	ret = waitpid(child_pid, &status, WUNTRACED);
-	if ((ret != child_pid) || !(WIFSTOPPED(status))) {
-		fprintf(stderr, "weird waitpid result %ld stat %x\n",
-				ret, status);
-		pkey_assert(0);
-	}
-	dprintf2("waitpid ret: %ld\n", ret);
-	dprintf2("waitpid status: %d\n", status);
-
-	pkey_access_deny(pkey);
-	pkey_write_deny(pkey);
-
-	/* Write access, untested for now:
-	ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
-	pkey_assert(ret != -1);
-	dprintf1("poke at %p: %ld\n", peek_at, ret);
-	*/
-
-	/*
-	 * Try to access the pkey-protected "ptr" via ptrace:
-	 */
-	ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
-	/* expect it to work, without an error: */
-	pkey_assert(ret != -1);
-	/* Now access from the current task, and expect an exception: */
-	peek_result = read_ptr(ptr);
-	expected_pk_fault(pkey);
-
-	/*
-	 * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
-	 */
-	ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
-	/* expect it to work, without an error: */
-	pkey_assert(ret != -1);
-	/* Now access from the current task, and expect NO exception: */
-	peek_result = read_ptr(plain_ptr);
-	do_not_expect_pk_fault();
-
-	ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
-	pkey_assert(ret != -1);
-
-	ret = kill(child_pid, SIGKILL);
-	pkey_assert(ret != -1);
-
-	wait(&status);
-
-	free(plain_ptr_unaligned);
-}
-
-void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
-{
-	void *p1;
-	int scratch;
-	int ptr_contents;
-	int ret;
-
-	p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
-	dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
-	/* lots_o_noops_around_write should be page-aligned already */
-	assert(p1 == &lots_o_noops_around_write);
-
-	/* Point 'p1' at the *second* page of the function: */
-	p1 += PAGE_SIZE;
-
-	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
-	lots_o_noops_around_write(&scratch);
-	ptr_contents = read_ptr(p1);
-	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
-
-	ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
-	pkey_assert(!ret);
-	pkey_access_deny(pkey);
-
-	dprintf2("pkru: %x\n", rdpkru());
-
-	/*
-	 * Make sure this is an *instruction* fault
-	 */
-	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
-	lots_o_noops_around_write(&scratch);
-	do_not_expect_pk_fault();
-	ptr_contents = read_ptr(p1);
-	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
-	expected_pk_fault(pkey);
-}
-
-void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
-{
-	int size = PAGE_SIZE;
-	int sret;
-
-	if (cpu_has_pku()) {
-		dprintf1("SKIP: %s: no CPU support\n", __func__);
-		return;
-	}
-
-	sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
-	pkey_assert(sret < 0);
-}
-
-void (*pkey_tests[])(int *ptr, u16 pkey) = {
-	test_read_of_write_disabled_region,
-	test_read_of_access_disabled_region,
-	test_write_of_write_disabled_region,
-	test_write_of_access_disabled_region,
-	test_kernel_write_of_access_disabled_region,
-	test_kernel_write_of_write_disabled_region,
-	test_kernel_gup_of_access_disabled_region,
-	test_kernel_gup_write_to_write_disabled_region,
-	test_executing_on_unreadable_memory,
-	test_ptrace_of_child,
-	test_pkey_syscalls_on_non_allocated_pkey,
-	test_pkey_syscalls_bad_args,
-	test_pkey_alloc_exhaust,
-};
-
-void run_tests_once(void)
-{
-	int *ptr;
-	int prot = PROT_READ|PROT_WRITE;
-
-	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
-		int pkey;
-		int orig_pkru_faults = pkru_faults;
-
-		dprintf1("======================\n");
-		dprintf1("test %d preparing...\n", test_nr);
-
-		tracing_on();
-		pkey = alloc_random_pkey();
-		dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
-		ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
-		dprintf1("test %d starting...\n", test_nr);
-		pkey_tests[test_nr](ptr, pkey);
-		dprintf1("freeing test memory: %p\n", ptr);
-		free_pkey_malloc(ptr);
-		sys_pkey_free(pkey);
-
-		dprintf1("pkru_faults: %d\n", pkru_faults);
-		dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
-
-		tracing_off();
-		close_test_fds();
-
-		printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
-		dprintf1("======================\n\n");
-	}
-	iteration_nr++;
-}
-
-void pkey_setup_shadow(void)
-{
-	shadow_pkru = __rdpkru();
-}
-
-int main(void)
-{
-	int nr_iterations = 22;
-
-	setup_handlers();
-
-	printf("has pku: %d\n", cpu_has_pku());
-
-	if (!cpu_has_pku()) {
-		int size = PAGE_SIZE;
-		int *ptr;
-
-		printf("running PKEY tests for unsupported CPU/OS\n");
-
-		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-		assert(ptr != (void *)-1);
-		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
-		exit(0);
-	}
-
-	pkey_setup_shadow();
-	printf("startup pkru: %x\n", rdpkru());
-	setup_hugetlbfs();
-
-	while (nr_iterations-- > 0)
-		run_tests_once();
-
-	printf("done (all tests OK)\n");
-	return 0;
-}
-- 
1.8.3.1

[RFC v3 20/23] selftest: PowerPC specific test updates to memory protection keys

[Ram Pai]

Abstracted out the arch specific code into the header file, and
added powerpc specific changes.

a) added 4k-backed hpte, memory allocator, powerpc specific.
b) added three test case where the key is associated after the page is
	accessed/allocated/mapped.
c) cleaned up the code to make checkpatch.pl happy

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 tools/testing/selftests/vm/pkey-helpers.h    | 230 +++++++++--
 tools/testing/selftests/vm/protection_keys.c | 562 ++++++++++++++++-----------
 2 files changed, 513 insertions(+), 279 deletions(-)

diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
index b202939..69bfa89 100644
--- a/tools/testing/selftests/vm/pkey-helpers.h
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -12,13 +12,72 @@
 #include <ucontext.h>
 #include <sys/mman.h>
 
-#define NR_PKEYS 16
-#define PKRU_BITS_PER_PKEY 2
+/* Define some kernel-like types */
+#define  u8 uint8_t
+#define u16 uint16_t
+#define u32 uint32_t
+#define u64 uint64_t
+
+#ifdef __i386__ /* arch */
+
+#define SYS_mprotect_key 380
+#define SYS_pkey_alloc	 381
+#define SYS_pkey_free	 382
+#define REG_IP_IDX REG_EIP
+#define si_pkey_offset 0x14
+
+#define NR_PKEYS		16
+#define NR_RESERVED_PKEYS	1
+#define PKRU_BITS_PER_PKEY	2
+#define PKEY_DISABLE_ACCESS	0x1
+#define PKEY_DISABLE_WRITE	0x2
+#define HPAGE_SIZE		(1UL<<21)
+
+#define INIT_PRKU 0x0UL
+
+#elif __powerpc64__ /* arch */
+
+#define SYS_mprotect_key 386
+#define SYS_pkey_alloc	 384
+#define SYS_pkey_free	 385
+#define si_pkey_offset	0x20
+#define REG_IP_IDX PT_NIP
+#define REG_TRAPNO PT_TRAP
+#define REG_AMR		45
+#define gregs gp_regs
+#define fpregs fp_regs
+
+#define NR_PKEYS		32
+#define NR_RESERVED_PKEYS	3
+#define PKRU_BITS_PER_PKEY	2
+#define PKEY_DISABLE_ACCESS	0x3  /* disable read and write */
+#define PKEY_DISABLE_WRITE	0x2
+#define HPAGE_SIZE		(1UL<<24)
+
+#define INIT_PRKU 0x3UL
+#else /* arch */
+
+	NOT SUPPORTED
+
+#endif /* arch */
+
 
 #ifndef DEBUG_LEVEL
 #define DEBUG_LEVEL 0
 #endif
 #define DPRINT_IN_SIGNAL_BUF_SIZE 4096
+
+
+static inline u32 pkey_to_shift(int pkey)
+{
+#ifdef __i386__ /* arch */
+	return pkey * PKRU_BITS_PER_PKEY;
+#elif __powerpc64__ /* arch */
+	return (NR_PKEYS - pkey - 1) * PKRU_BITS_PER_PKEY;
+#endif /* arch */
+}
+
+
 extern int dprint_in_signal;
 extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
 static inline void sigsafe_printf(const char *format, ...)
@@ -53,53 +112,76 @@ static inline void sigsafe_printf(const char *format, ...)
 #define dprintf3(args...) dprintf_level(3, args)
 #define dprintf4(args...) dprintf_level(4, args)
 
-extern unsigned int shadow_pkru;
-static inline unsigned int __rdpkru(void)
+extern u64 shadow_pkey_reg;
+
+static inline u64 __rdpkey_reg(void)
 {
+#ifdef __i386__ /* arch */
 	unsigned int eax, edx;
 	unsigned int ecx = 0;
-	unsigned int pkru;
+	unsigned int pkey_reg;
 
 	asm volatile(".byte 0x0f,0x01,0xee\n\t"
 		     : "=a" (eax), "=d" (edx)
 		     : "c" (ecx));
-	pkru = eax;
-	return pkru;
+#elif __powerpc64__ /* arch */
+	u64 eax;
+	u64 pkey_reg;
+
+	asm volatile("mfspr %0, 0xd" : "=r" ((u64)(eax)));
+#endif /* arch */
+	pkey_reg = (u64)eax;
+	return pkey_reg;
 }
 
-static inline unsigned int _rdpkru(int line)
+static inline u64 _rdpkey_reg(int line)
 {
-	unsigned int pkru = __rdpkru();
+	u64 pkey_reg = __rdpkey_reg();
 
-	dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
-			line, pkru, shadow_pkru);
-	assert(pkru == shadow_pkru);
+	dprintf4("rdpkey_reg(line=%d) pkey_reg: %lx shadow: %lx\n",
+			line, pkey_reg, shadow_pkey_reg);
+	assert(pkey_reg == shadow_pkey_reg);
 
-	return pkru;
+	return pkey_reg;
 }
 
-#define rdpkru() _rdpkru(__LINE__)
+#define rdpkey_reg() _rdpkey_reg(__LINE__)
 
-static inline void __wrpkru(unsigned int pkru)
+static inline void __wrpkey_reg(u64 pkey_reg)
 {
-	unsigned int eax = pkru;
+#ifdef __i386__ /* arch */
+	unsigned int eax = pkey_reg;
 	unsigned int ecx = 0;
 	unsigned int edx = 0;
 
-	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+	dprintf4("%s() changing %lx to %lx\n",
+			 __func__, __rdpkey_reg(), pkey_reg);
 	asm volatile(".byte 0x0f,0x01,0xef\n\t"
 		     : : "a" (eax), "c" (ecx), "d" (edx));
-	assert(pkru == __rdpkru());
+	dprintf4("%s() PKRUP after changing %lx to %lx\n",
+			__func__, __rdpkey_reg(), pkey_reg);
+#else /* arch */
+	u64 eax = pkey_reg;
+
+	dprintf4("%s() changing %llx to %llx\n",
+			 __func__, __rdpkey_reg(), pkey_reg);
+	asm volatile("mtspr 0xd, %0" : : "r" ((unsigned long)(eax)) : "memory");
+	dprintf4("%s() PKRUP after changing %llx to %llx\n",
+			 __func__, __rdpkey_reg(), pkey_reg);
+#endif /* arch */
+	assert(pkey_reg == __rdpkey_reg());
 }
 
-static inline void wrpkru(unsigned int pkru)
+static inline void wrpkey_reg(u64 pkey_reg)
 {
-	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+	dprintf4("%s() changing %lx to %lx\n",
+			__func__, __rdpkey_reg(), pkey_reg);
 	/* will do the shadow check for us: */
-	rdpkru();
-	__wrpkru(pkru);
-	shadow_pkru = pkru;
-	dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
+	rdpkey_reg();
+	__wrpkey_reg(pkey_reg);
+	shadow_pkey_reg = pkey_reg;
+	dprintf4("%s(%lx) pkey_reg: %lx\n",
+		__func__, pkey_reg, __rdpkey_reg());
 }
 
 /*
@@ -108,40 +190,37 @@ static inline void wrpkru(unsigned int pkru)
  */
 static inline void __pkey_access_allow(int pkey, int do_allow)
 {
-	unsigned int pkru = rdpkru();
+	u64 pkey_reg = rdpkey_reg();
 	int bit = pkey * 2;
 
 	if (do_allow)
-		pkru &= (1<<bit);
+		pkey_reg &= (1<<bit);
 	else
-		pkru |= (1<<bit);
+		pkey_reg |= (1<<bit);
 
-	dprintf4("pkru now: %08x\n", rdpkru());
-	wrpkru(pkru);
+	dprintf4("pkey_reg now: %lx\n", rdpkey_reg());
+	wrpkey_reg(pkey_reg);
 }
 
 static inline void __pkey_write_allow(int pkey, int do_allow_write)
 {
-	long pkru = rdpkru();
+	u64 pkey_reg = rdpkey_reg();
 	int bit = pkey * 2 + 1;
 
 	if (do_allow_write)
-		pkru &= (1<<bit);
+		pkey_reg &= (1<<bit);
 	else
-		pkru |= (1<<bit);
+		pkey_reg |= (1<<bit);
 
-	wrpkru(pkru);
-	dprintf4("pkru now: %08x\n", rdpkru());
+	wrpkey_reg(pkey_reg);
+	dprintf4("pkey_reg now: %lx\n", rdpkey_reg());
 }
 
-#define PROT_PKEY0     0x10            /* protection key value (bit 0) */
-#define PROT_PKEY1     0x20            /* protection key value (bit 1) */
-#define PROT_PKEY2     0x40            /* protection key value (bit 2) */
-#define PROT_PKEY3     0x80            /* protection key value (bit 3) */
-
-#define PAGE_SIZE 4096
 #define MB	(1<<20)
 
+#ifdef __i386__ /* arch */
+
+#define PAGE_SIZE 4096
 static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
 		unsigned int *ecx, unsigned int *edx)
 {
@@ -159,7 +238,7 @@ static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
 #define X86_FEATURE_PKU        (1<<3) /* Protection Keys for Userspace */
 #define X86_FEATURE_OSPKE      (1<<4) /* OS Protection Keys Enable */
 
-static inline int cpu_has_pku(void)
+static inline int cpu_has_pkey(void)
 {
 	unsigned int eax;
 	unsigned int ebx;
@@ -183,7 +262,6 @@ static inline int cpu_has_pku(void)
 
 #define XSTATE_PKRU_BIT	(9)
 #define XSTATE_PKRU	0x200
-
 int pkru_xstate_offset(void)
 {
 	unsigned int eax;
@@ -216,4 +294,72 @@ int pkru_xstate_offset(void)
 	return xstate_offset;
 }
 
+/* 8-bytes of instruction * 512 bytes = 1 page */
+#define __page_o_noops() asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr")
+
+#elif __powerpc64__ /* arch */
+
+#define PAGE_SIZE (0x1UL << 16)
+static inline int cpu_has_pkey(void)
+{
+	return 1;
+}
+
+/* 8-bytes of instruction * 16384bytes = 1 page */
+#define __page_o_noops() asm(".rept 16384 ; nop; .endr")
+
+#endif /* arch */
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+#define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
+#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
+#define ALIGN_PTR_UP(p, ptr_align_to)	\
+		((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
+#define ALIGN_PTR_DOWN(p, ptr_align_to) \
+	((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
+#define __stringify_1(x...)     #x
+#define __stringify(x...)       __stringify_1(x)
+
+#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+
+extern void abort_hooks(void);
+#define pkey_assert(condition) do {		\
+	if (!(condition)) {			\
+		dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
+				__FILE__, __LINE__,	\
+				test_nr, iteration_nr);	\
+		dprintf0("errno at assert: %d", errno);	\
+		abort_hooks();			\
+		assert(condition);		\
+	}					\
+} while (0)
+#define raw_assert(cond) assert(cond)
+
+
+static inline int open_hugepage_file(int flag)
+{
+	int fd;
+#ifdef __i386__ /* arch */
+	fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages",
+		 O_RDONLY);
+#elif __powerpc64__ /* arch */
+	fd = open("/sys/kernel/mm/hugepages/hugepages-16384kB/nr_hugepages",
+		O_RDONLY);
+#else /* arch */
+	NOT SUPPORTED
+#endif /* arch */
+	return fd;
+}
+
+static inline int get_start_key(void)
+{
+#ifdef __i386__ /* arch */
+	return 1;
+#elif __powerpc64__ /* arch */
+	return 0;
+#else /* arch */
+	NOT SUPPORTED
+#endif /* arch */
+}
+
 #endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 3237bc0..08b83ca 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -1,10 +1,10 @@
 /*
- * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
+ * Tests Memory Protection Keys (see Documentation/vm/protection-keys.txt)
  *
  * There are examples in here of:
  *  * how to set protection keys on memory
- *  * how to set/clear bits in PKRU (the rights register)
- *  * how to handle SEGV_PKRU signals and extract pkey-relevant
+ *  * how to set/clear bits in Protection Key registers (the rights register)
+ *  * how to handle SEGV_PKUERR signals and extract pkey-relevant
  *    information from the siginfo
  *
  * Things to add:
@@ -12,17 +12,23 @@
  *	prefault pages in at malloc, or not
  *	protect MPX bounds tables with protection keys?
  *	make sure VMA splitting/merging is working correctly
- *	OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
- *	look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
- *	do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
+ *	OOMs can destroy mm->mmap (see exit_mmap()),
+ *			so make sure it is immune to pkeys
+ *	look for pkey "leaks" where it is still set on a VMA
+ *			 but "freed" back to the kernel
+ *	do a plain mprotect() to a mprotect_pkey() area and make
+ *			 sure the pkey sticks
  *
  * Compile like this:
- *	gcc      -o protection_keys    -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- *	gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ *	gcc      -o protection_keys    -O2 -g -std=gnu99
+ *			 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ *	gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99
+ *			 -pthread -Wall protection_keys.c -lrt -ldl -lm
  */
 #define _GNU_SOURCE
 #include <errno.h>
 #include <linux/futex.h>
+#include <time.h>
 #include <sys/time.h>
 #include <sys/syscall.h>
 #include <string.h>
@@ -46,36 +52,11 @@
 
 int iteration_nr = 1;
 int test_nr;
-
-unsigned int shadow_pkru;
-
-#define HPAGE_SIZE	(1UL<<21)
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
-#define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
-#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
-#define ALIGN_PTR_UP(p, ptr_align_to)	((typeof(p))ALIGN_UP((unsigned long)(p),	ptr_align_to))
-#define ALIGN_PTR_DOWN(p, ptr_align_to)	((typeof(p))ALIGN_DOWN((unsigned long)(p),	ptr_align_to))
-#define __stringify_1(x...)     #x
-#define __stringify(x...)       __stringify_1(x)
-
-#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+u64 shadow_pkey_reg;
 
 int dprint_in_signal;
 char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
 
-extern void abort_hooks(void);
-#define pkey_assert(condition) do {		\
-	if (!(condition)) {			\
-		dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
-				__FILE__, __LINE__,	\
-				test_nr, iteration_nr);	\
-		dprintf0("errno at assert: %d", errno);	\
-		abort_hooks();			\
-		assert(condition);		\
-	}					\
-} while (0)
-#define raw_assert(cond) assert(cond)
-
 void cat_into_file(char *str, char *file)
 {
 	int fd = open(file, O_RDWR);
@@ -153,11 +134,6 @@ void abort_hooks(void)
 #endif
 }
 
-static inline void __page_o_noops(void)
-{
-	/* 8-bytes of instruction * 512 bytes = 1 page */
-	asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
-}
 
 /*
  * This attempts to have roughly a page of instructions followed by a few
@@ -181,26 +157,6 @@ void lots_o_noops_around_write(int *write_to_me)
 	dprintf3("%s() done\n", __func__);
 }
 
-/* Define some kernel-like types */
-#define  u8 uint8_t
-#define u16 uint16_t
-#define u32 uint32_t
-#define u64 uint64_t
-
-#ifdef __i386__
-#define SYS_mprotect_key 380
-#define SYS_pkey_alloc	 381
-#define SYS_pkey_free	 382
-#define REG_IP_IDX REG_EIP
-#define si_pkey_offset 0x14
-#else
-#define SYS_mprotect_key 329
-#define SYS_pkey_alloc	 330
-#define SYS_pkey_free	 331
-#define REG_IP_IDX REG_RIP
-#define si_pkey_offset 0x20
-#endif
-
 void dump_mem(void *dumpme, int len_bytes)
 {
 	char *c = (void *)dumpme;
@@ -208,6 +164,7 @@ void dump_mem(void *dumpme, int len_bytes)
 
 	for (i = 0; i < len_bytes; i += sizeof(u64)) {
 		u64 *ptr = (u64 *)(c + i);
+
 		dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
 	}
 }
@@ -229,29 +186,48 @@ static char *si_code_str(int si_code)
 	return "UNKNOWN";
 }
 
-int pkru_faults;
+int pkey_faults;
 int last_si_pkey = -1;
+
+u64 reset_bits(int pkey, u64 bits)
+{
+	u32 shift = pkey_to_shift(pkey);
+
+	return ~(bits << shift);
+}
+
+u64 left_shift_bits(int pkey, u64 bits)
+{
+	u32 shift = pkey_to_shift(pkey);
+
+	return (bits << shift);
+}
+
+u64 right_shift_bits(int pkey, u64 bits)
+{
+	u32 shift = pkey_to_shift(pkey);
+
+	return (bits >> shift);
+}
+
 void signal_handler(int signum, siginfo_t *si, void *vucontext)
 {
 	ucontext_t *uctxt = vucontext;
 	int trapno;
 	unsigned long ip;
 	char *fpregs;
-	u32 *pkru_ptr;
+	u64 *pkey_reg_ptr;
 	u64 si_pkey;
 	u32 *si_pkey_ptr;
-	int pkru_offset;
-	fpregset_t fpregset;
 
 	dprint_in_signal = 1;
 	dprintf1(">>>>===============SIGSEGV============================\n");
-	dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
-			__rdpkru(), shadow_pkru);
+	dprintf1("%s()::%d, pkey_reg: 0x%lx shadow: %lx\n", __func__, __LINE__,
+			__rdpkey_reg(), shadow_pkey_reg);
 
 	trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
 	ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
-	fpregset = uctxt->uc_mcontext.fpregs;
-	fpregs = (void *)fpregset;
+	fpregs = (char *) uctxt->uc_mcontext.fpregs;
 
 	dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
 			trapno, ip, si_code_str(si->si_code), si->si_code);
@@ -262,20 +238,22 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
 	 * state.  We just assume that it is here.
 	 */
 	fpregs += 0x70;
-#endif
-	pkru_offset = pkru_xstate_offset();
-	pkru_ptr = (void *)(&fpregs[pkru_offset]);
-
-	dprintf1("siginfo: %p\n", si);
-	dprintf1(" fpregs: %p\n", fpregs);
+	pkey_reg_ptr = (void *)(&fpregs[pkru_xstate_offset()]);
 	/*
-	 * If we got a PKRU fault, we *HAVE* to have at least one bit set in
+	 * If we got a key fault, we *HAVE* to have at least one bit set in
 	 * here.
 	 */
 	dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
 	if (DEBUG_LEVEL > 4)
-		dump_mem(pkru_ptr - 128, 256);
-	pkey_assert(*pkru_ptr);
+		dump_mem(pkey_reg_ptr - 128, 256);
+#elif __powerpc64__
+	pkey_reg_ptr = &uctxt->uc_mcontext.gregs[REG_AMR];
+#endif
+
+
+	dprintf1("siginfo: %p\n", si);
+	dprintf1(" fpregs: %p\n", fpregs);
+	pkey_assert(*pkey_reg_ptr);
 
 	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
 	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
@@ -291,36 +269,25 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
 		exit(4);
 	}
 
-	dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
-	/* need __rdpkru() version so we do not do shadow_pkru checking */
-	dprintf1("signal pkru from  pkru: %08x\n", __rdpkru());
+	dprintf1("signal pkey_reg : %08x\n", *pkey_reg_ptr);
+	/*
+	 * need __rdpkey_reg() version so we do not do
+	 * shadow_pkey_reg checking
+	 */
+	dprintf1("signal pkey_reg from  pkey_reg: %08x\n", __rdpkey_reg());
 	dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
-	*(u64 *)pkru_ptr = 0x00000000;
-	dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
-	pkru_faults++;
+	*(u64 *)pkey_reg_ptr &= reset_bits(si_pkey, PKEY_DISABLE_ACCESS);
+	shadow_pkey_reg &= reset_bits(si_pkey, PKEY_DISABLE_ACCESS);
+	dprintf1("WARNING: set PRKU=0 to allow faulting instruction "
+			"to continue\n");
+	pkey_faults++;
 	dprintf1("<<<<==================================================\n");
-	return;
-	if (trapno == 14) {
-		fprintf(stderr,
-			"ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
-			trapno, ip);
-		fprintf(stderr, "si_addr %p\n", si->si_addr);
-		fprintf(stderr, "REG_ERR: %lx\n",
-				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
-		exit(1);
-	} else {
-		fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
-		fprintf(stderr, "si_addr %p\n", si->si_addr);
-		fprintf(stderr, "REG_ERR: %lx\n",
-				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
-		exit(2);
-	}
-	dprint_in_signal = 0;
 }
 
 int wait_all_children(void)
 {
 	int status;
+
 	return waitpid(-1, &status, 0);
 }
 
@@ -409,51 +376,50 @@ void dumpit(char *f)
 	close(fd);
 }
 
-#define PKEY_DISABLE_ACCESS    0x1
-#define PKEY_DISABLE_WRITE     0x2
-
-u32 pkey_get(int pkey, unsigned long flags)
+u64 pkey_get(int pkey, unsigned long flags)
 {
-	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
-	u32 pkru = __rdpkru();
-	u32 shifted_pkru;
-	u32 masked_pkru;
+	u64 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+	u64 pkey_reg = __rdpkey_reg();
+	u64 shifted_pkey_reg;
+	u64 masked_pkey_reg;
 
 	dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
 			__func__, pkey, flags, 0, 0);
-	dprintf2("%s() raw pkru: %x\n", __func__, pkru);
+	dprintf2("%s() raw pkey_reg: %lx\n", __func__, pkey_reg);
 
-	shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
-	dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
-	masked_pkru = shifted_pkru & mask;
-	dprintf2("%s() masked  pkru: %x\n", __func__, masked_pkru);
+	shifted_pkey_reg = right_shift_bits(pkey, pkey_reg);
+	dprintf2("%s() shifted_pkey_reg: %lx\n", __func__, shifted_pkey_reg);
+	masked_pkey_reg = shifted_pkey_reg & mask;
+	dprintf2("%s() masked  pkey_reg: %lx\n", __func__, masked_pkey_reg);
 	/*
 	 * shift down the relevant bits to the lowest two, then
 	 * mask off all the other high bits.
 	 */
-	return masked_pkru;
+	return masked_pkey_reg;
 }
 
 int pkey_set(int pkey, unsigned long rights, unsigned long flags)
 {
-	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
-	u32 old_pkru = __rdpkru();
-	u32 new_pkru;
+	u64 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+	u64 old_pkey_reg = __rdpkey_reg();
+	u64 new_pkey_reg;
 
 	/* make sure that 'rights' only contains the bits we expect: */
 	assert(!(rights & ~mask));
 
-	/* copy old pkru */
-	new_pkru = old_pkru;
+	/* copy old pkey_reg */
+	new_pkey_reg = old_pkey_reg;
 	/* mask out bits from pkey in old value: */
-	new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
+	new_pkey_reg &= reset_bits(pkey, mask);
 	/* OR in new bits for pkey: */
-	new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
+	new_pkey_reg |= left_shift_bits(pkey, rights);
 
-	__wrpkru(new_pkru);
+	__wrpkey_reg(new_pkey_reg);
 
-	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
-			__func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
+	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x "
+			"pkey_reg now: %x old_pkey_reg: %x\n",
+			__func__, pkey, rights, flags,
+			0, __rdpkey_reg(), old_pkey_reg);
 	return 0;
 }
 
@@ -461,8 +427,8 @@ void pkey_disable_set(int pkey, int flags)
 {
 	unsigned long syscall_flags = 0;
 	int ret;
-	int pkey_rights;
-	u32 orig_pkru = rdpkru();
+	u64 pkey_rights;
+	u64 orig_pkey_reg = rdpkey_reg();
 
 	dprintf1("START->%s(%d, 0x%x)\n", __func__,
 		pkey, flags);
@@ -474,23 +440,28 @@ void pkey_disable_set(int pkey, int flags)
 			pkey, pkey, pkey_rights);
 	pkey_assert(pkey_rights >= 0);
 
-	pkey_rights |= flags;
+	/* process flags only if they have some new bits enabled */
+	if (flags && !(pkey_rights & flags)) {
+		pkey_rights |= flags;
 
-	ret = pkey_set(pkey, pkey_rights, syscall_flags);
-	assert(!ret);
-	/*pkru and flags have the same format */
-	shadow_pkru |= flags << (pkey * 2);
-	dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
+		ret = pkey_set(pkey, pkey_rights, syscall_flags);
+		assert(!ret);
+		/*pkey_reg and flags have the same format */
+		shadow_pkey_reg |= left_shift_bits(pkey, flags);
+		dprintf1("%s(%d) shadow: 0x%x\n",
+			__func__, pkey, shadow_pkey_reg);
 
-	pkey_assert(ret >= 0);
+		pkey_assert(ret >= 0);
 
-	pkey_rights = pkey_get(pkey, syscall_flags);
-	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
-			pkey, pkey, pkey_rights);
+		pkey_rights = pkey_get(pkey, syscall_flags);
+		dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+				pkey, pkey, pkey_rights);
 
-	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
-	if (flags)
-		pkey_assert(rdpkru() > orig_pkru);
+		dprintf1("%s(%d) pkey_reg: 0x%lx\n",
+			__func__, pkey, rdpkey_reg());
+		if (flags)
+			pkey_assert(rdpkey_reg() > orig_pkey_reg);
+	}
 	dprintf1("END<---%s(%d, 0x%x)\n", __func__,
 		pkey, flags);
 }
@@ -499,8 +470,8 @@ void pkey_disable_clear(int pkey, int flags)
 {
 	unsigned long syscall_flags = 0;
 	int ret;
-	int pkey_rights = pkey_get(pkey, syscall_flags);
-	u32 orig_pkru = rdpkru();
+	u64 pkey_rights = pkey_get(pkey, syscall_flags);
+	u64 orig_pkey_reg = rdpkey_reg();
 
 	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
 
@@ -508,20 +479,21 @@ void pkey_disable_clear(int pkey, int flags)
 			pkey, pkey, pkey_rights);
 	pkey_assert(pkey_rights >= 0);
 
-	pkey_rights |= flags;
+	pkey_rights &= ~flags;
 
 	ret = pkey_set(pkey, pkey_rights, 0);
-	/* pkru and flags have the same format */
-	shadow_pkru &= ~(flags << (pkey * 2));
+	/* pkey_reg and flags have the same format */
+	shadow_pkey_reg &= reset_bits(pkey, flags);
 	pkey_assert(ret >= 0);
 
 	pkey_rights = pkey_get(pkey, syscall_flags);
 	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
 			pkey, pkey, pkey_rights);
 
-	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+	dprintf1("%s(%d) pkey_reg: 0x%x\n",
+			__func__, pkey, rdpkey_reg());
 	if (flags)
-		assert(rdpkru() > orig_pkru);
+		assert(rdpkey_reg() > orig_pkey_reg);
 }
 
 void pkey_write_allow(int pkey)
@@ -564,49 +536,72 @@ int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
 int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
 {
 	int ret = syscall(SYS_pkey_alloc, flags, init_val);
+
 	dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
 			__func__, flags, init_val, ret, errno);
 	return ret;
 }
 
+void pkey_setup_shadow(void)
+{
+	shadow_pkey_reg = __rdpkey_reg();
+}
+
+void pkey_reset_shadow(u32 key)
+{
+	shadow_pkey_reg &= reset_bits(key, 0x3);
+}
+
+void pkey_set_shadow(u32 key, u64 init_val)
+{
+	shadow_pkey_reg |=  left_shift_bits(key, init_val);
+}
+
 int alloc_pkey(void)
 {
 	int ret;
-	unsigned long init_val = 0x0;
+	u64 init_val = 0x0;
 
-	dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
-			__LINE__, __rdpkru(), shadow_pkru);
+	dprintf1("%s()::%d, pkey_reg: 0x%x shadow: %x\n",
+			__func__, __LINE__, __rdpkey_reg(),
+			shadow_pkey_reg);
 	ret = sys_pkey_alloc(0, init_val);
 	/*
-	 * pkey_alloc() sets PKRU, so we need to reflect it in
-	 * shadow_pkru:
+	 * pkey_alloc() sets pkey register, so we need to reflect it in
+	 * shadow_pkey_reg:
 	 */
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+		__func__, __LINE__, ret, __rdpkey_reg(),
+		shadow_pkey_reg);
 	if (ret) {
 		/* clear both the bits: */
-		shadow_pkru &= ~(0x3      << (ret * 2));
-		dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-				__LINE__, ret, __rdpkru(), shadow_pkru);
+		pkey_reset_shadow(ret);
+		dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow:"
+				" 0x%x\n",
+			__func__, __LINE__, ret,
+			__rdpkey_reg(), shadow_pkey_reg);
 		/*
 		 * move the new state in from init_val
-		 * (remember, we cheated and init_val == pkru format)
+		 * (remember, we cheated and init_val == pkey_reg format)
 		 */
-		shadow_pkru |=  (init_val << (ret * 2));
+		pkey_set_shadow(ret, init_val);
 	}
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
-	dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
+	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+			__func__, __LINE__, ret, __rdpkey_reg(),
+			shadow_pkey_reg);
+	dprintf1("%s()::%d errno: %d\n", __func__, __LINE__, errno);
 	/* for shadow checking: */
-	rdpkru();
-	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+	rdpkey_reg();
+	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+			__func__, __LINE__, ret, __rdpkey_reg(),
+			shadow_pkey_reg);
 	return ret;
 }
 
 int sys_pkey_free(unsigned long pkey)
 {
 	int ret = syscall(SYS_pkey_free, pkey);
+
 	dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
 	return ret;
 }
@@ -624,13 +619,15 @@ int alloc_random_pkey(void)
 	int alloced_pkeys[NR_PKEYS];
 	int nr_alloced = 0;
 	int random_index;
+
 	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+	srand((unsigned int)time(NULL));
 
 	/* allocate every possible key and make a note of which ones we got */
 	max_nr_pkey_allocs = NR_PKEYS;
-	max_nr_pkey_allocs = 1;
 	for (i = 0; i < max_nr_pkey_allocs; i++) {
 		int new_pkey = alloc_pkey();
+
 		if (new_pkey < 0)
 			break;
 		alloced_pkeys[nr_alloced++] = new_pkey;
@@ -646,13 +643,14 @@ int alloc_random_pkey(void)
 	/* go through the allocated ones that we did not want and free them */
 	for (i = 0; i < nr_alloced; i++) {
 		int free_ret;
+
 		if (!alloced_pkeys[i])
 			continue;
 		free_ret = sys_pkey_free(alloced_pkeys[i]);
 		pkey_assert(!free_ret);
 	}
-	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+	dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkey_reg(), shadow_pkey_reg);
 	return ret;
 }
 
@@ -664,17 +662,22 @@ int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
 
 	while (0) {
 		int rpkey = alloc_random_pkey();
+
 		ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
-		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+
+		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) "
+				"ret: %d\n",
 				ptr, size, orig_prot, pkey, ret);
 		if (nr_iterations-- < 0)
 			break;
 
-		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+		dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+			__func__, __LINE__, ret, __rdpkey_reg(),
+			shadow_pkey_reg);
 		sys_pkey_free(rpkey);
-		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+		dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+			__func__, __LINE__, ret, __rdpkey_reg(),
+			shadow_pkey_reg);
 	}
 	pkey_assert(pkey < NR_PKEYS);
 
@@ -682,8 +685,8 @@ int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
 	dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
 			ptr, size, orig_prot, pkey, ret);
 	pkey_assert(!ret);
-	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-			__LINE__, ret, __rdpkru(), shadow_pkru);
+	dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n", __func__,
+			__LINE__, ret, __rdpkey_reg(), shadow_pkey_reg);
 	return ret;
 }
 
@@ -708,7 +711,9 @@ void record_pkey_malloc(void *ptr, long size)
 		/* every record is full */
 		size_t old_nr_records = nr_pkey_malloc_records;
 		size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
-		size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
+		size_t new_size = new_nr_records *
+				sizeof(struct pkey_malloc_record);
+
 		dprintf2("new_nr_records: %zd\n", new_nr_records);
 		dprintf2("new_size: %zd\n", new_size);
 		pkey_malloc_records = realloc(pkey_malloc_records, new_size);
@@ -732,9 +737,11 @@ void free_pkey_malloc(void *ptr)
 {
 	long i;
 	int ret;
+
 	dprintf3("%s(%p)\n", __func__, ptr);
 	for (i = 0; i < nr_pkey_malloc_records; i++) {
 		struct pkey_malloc_record *rec = &pkey_malloc_records[i];
+
 		dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
 				ptr, i, rec, rec->ptr, rec->size);
 		if ((ptr <  rec->ptr) ||
@@ -761,16 +768,46 @@ void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
 	void *ptr;
 	int ret;
 
-	rdpkru();
+	rdpkey_reg();
+	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+			size, prot, pkey);
+	pkey_assert(pkey < NR_PKEYS);
+	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+	pkey_assert(ptr != (void *)-1);
+	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+	pkey_assert(!ret);
+	record_pkey_malloc(ptr, size);
+	rdpkey_reg();
+
+	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+	return ptr;
+}
+
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+	void *ptr;
+	int ret;
+
+#ifdef __powerpc64__
+	return PTR_ERR_ENOTSUP;
+#endif /*  __powerpc64__ */
+	rdpkey_reg();
 	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
 			size, prot, pkey);
 	pkey_assert(pkey < NR_PKEYS);
 	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 	pkey_assert(ptr != (void *)-1);
+
+	ret = syscall(__NR_subpage_prot, ptr, size, NULL);
+	if (ret) {
+		perror("subpage_perm");
+		return PTR_ERR_ENOTSUP;
+	}
+
 	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
 	pkey_assert(!ret);
 	record_pkey_malloc(ptr, size);
-	rdpkru();
+	rdpkey_reg();
 
 	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
 	return ptr;
@@ -815,17 +852,19 @@ void setup_hugetlbfs(void)
 	char buf[] = "123";
 
 	if (geteuid() != 0) {
-		fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
+		fprintf(stderr,
+			"WARNING: not run as root, can not do hugetlb test\n");
 		return;
 	}
 
-	cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
+	cat_into_file(__stringify(GET_NR_HUGE_PAGES),
+			"/proc/sys/vm/nr_hugepages");
 
 	/*
 	 * Now go make sure that we got the pages and that they
 	 * are 2M pages.  Someone might have made 1G the default.
 	 */
-	fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
+	fd = open_hugepage_file(O_RDONLY);
 	if (fd < 0) {
 		perror("opening sysfs 2M hugetlb config");
 		return;
@@ -840,7 +879,8 @@ void setup_hugetlbfs(void)
 	}
 
 	if (atoi(buf) != GET_NR_HUGE_PAGES) {
-		fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
+		fprintf(stderr, "could not confirm 2M pages, got:"
+				" '%s' expected %d\n",
 			buf, GET_NR_HUGE_PAGES);
 		return;
 	}
@@ -895,12 +935,13 @@ void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
 void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
 
 	malloc_pkey_with_mprotect,
+	malloc_pkey_with_mprotect_subpage,
 	malloc_pkey_anon_huge,
 	malloc_pkey_hugetlb
 /* can not do direct with the pkey_mprotect() API:
-	malloc_pkey_mmap_direct,
-	malloc_pkey_mmap_dax,
-*/
+ * malloc_pkey_mmap_direct,
+ * malloc_pkey_mmap_dax,
+ */
 };
 
 void *malloc_pkey(long size, int prot, u16 pkey)
@@ -933,31 +974,32 @@ void *malloc_pkey(long size, int prot, u16 pkey)
 	return ret;
 }
 
-int last_pkru_faults;
-void expected_pk_fault(int pkey)
+int last_pkey_faults;
+void expected_pkey_faults(int pkey)
 {
-	dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
-			__func__, last_pkru_faults, pkru_faults);
+	dprintf2("%s(): last_pkey_faults: %d pkey_faults: %d\n",
+			__func__, last_pkey_faults, pkey_faults);
 	dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
-	pkey_assert(last_pkru_faults + 1 == pkru_faults);
+	pkey_assert(last_pkey_faults + 1 == pkey_faults);
 	pkey_assert(last_si_pkey == pkey);
 	/*
-	 * The signal handler shold have cleared out PKRU to let the
+	 * The signal handler shold have cleared out pkey-register to let the
 	 * test program continue.  We now have to restore it.
 	 */
-	if (__rdpkru() != 0)
+	if (__rdpkey_reg() != shadow_pkey_reg)
 		pkey_assert(0);
 
-	__wrpkru(shadow_pkru);
-	dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
-			__func__, shadow_pkru);
-	last_pkru_faults = pkru_faults;
+	__wrpkey_reg(shadow_pkey_reg);
+	dprintf1("%s() set pkey-register=%x to restore state "
+			" after signal nuked it\n",
+			__func__, shadow_pkey_reg);
+	last_pkey_faults = pkey_faults;
 	last_si_pkey = -1;
 }
 
 void do_not_expect_pk_fault(void)
 {
-	pkey_assert(last_pkru_faults == pkru_faults);
+	pkey_assert(last_pkey_faults == pkey_faults);
 }
 
 int test_fds[10] = { -1 };
@@ -973,6 +1015,7 @@ void __save_test_fd(int fd)
 int get_test_read_fd(void)
 {
 	int test_fd = open("/etc/passwd", O_RDONLY);
+
 	__save_test_fd(test_fd);
 	return test_fd;
 }
@@ -1009,32 +1052,76 @@ void test_read_of_write_disabled_region(int *ptr, u16 pkey)
 	ptr_contents = read_ptr(ptr);
 	dprintf1("*ptr: %d\n", ptr_contents);
 	dprintf1("\n");
+	do_not_expect_pk_fault();
 }
+
 void test_read_of_access_disabled_region(int *ptr, u16 pkey)
 {
 	int ptr_contents;
 
-	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
-	rdpkru();
+	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
+			 pkey, ptr);
+	rdpkey_reg();
 	pkey_access_deny(pkey);
 	ptr_contents = read_ptr(ptr);
 	dprintf1("*ptr: %d\n", ptr_contents);
-	expected_pk_fault(pkey);
+	expected_pkey_faults(pkey);
 }
+
+void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr,
+		u16 pkey)
+{
+	int ptr_contents;
+
+	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
+				pkey, ptr);
+	ptr_contents = read_ptr(ptr);
+	dprintf1("reading ptr before disabling the read : %d\n",
+			ptr_contents);
+	rdpkey_reg();
+	pkey_access_deny(pkey);
+	ptr_contents = read_ptr(ptr);
+	dprintf1("*ptr: %d\n", ptr_contents);
+	expected_pkey_faults(pkey);
+}
+
+void test_write_of_write_disabled_region_with_page_already_mapped(int *ptr,
+		u16 pkey)
+{
+	*ptr = __LINE__;
+	dprintf1("disabling write access; after accessing the page, "
+		"to PKEY[%02d], doing write\n", pkey);
+	pkey_write_deny(pkey);
+	*ptr = __LINE__;
+	expected_pkey_faults(pkey);
+}
+
 void test_write_of_write_disabled_region(int *ptr, u16 pkey)
 {
 	dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
 	pkey_write_deny(pkey);
 	*ptr = __LINE__;
-	expected_pk_fault(pkey);
+	expected_pkey_faults(pkey);
 }
 void test_write_of_access_disabled_region(int *ptr, u16 pkey)
 {
 	dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
 	pkey_access_deny(pkey);
 	*ptr = __LINE__;
-	expected_pk_fault(pkey);
+	expected_pkey_faults(pkey);
 }
+
+void test_write_of_access_disabled_region_with_page_already_mapped(int *ptr,
+			u16 pkey)
+{
+	*ptr = __LINE__;
+	dprintf1("disabling access; after accessing the page, "
+		" to PKEY[%02d], doing write\n", pkey);
+	pkey_access_deny(pkey);
+	*ptr = __LINE__;
+	expected_pkey_faults(pkey);
+}
+
 void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
 {
 	int ret;
@@ -1103,10 +1190,10 @@ void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
 void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
 {
 	int err;
-	int i;
+	int i = get_start_key();
 
 	/* Note: 0 is the default pkey, so don't mess with it */
-	for (i = 1; i < NR_PKEYS; i++) {
+	for (; i < NR_PKEYS; i++) {
 		if (pkey == i)
 			continue;
 
@@ -1126,7 +1213,7 @@ void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
 void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
 {
 	int err;
-	int bad_pkey = NR_PKEYS+99;
+	int bad_pkey = NR_PKEYS+pkey;
 
 	/* pass a known-invalid pkey in: */
 	err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
@@ -1136,21 +1223,24 @@ void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
 /* Assumes that all pkeys other than 'pkey' are unallocated */
 void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
 {
-	int err;
+	int err = 0;
 	int allocated_pkeys[NR_PKEYS] = {0};
 	int nr_allocated_pkeys = 0;
 	int i;
 
 	for (i = 0; i < NR_PKEYS*2; i++) {
 		int new_pkey;
+
 		dprintf1("%s() alloc loop: %d\n", __func__, i);
 		new_pkey = alloc_pkey();
-		dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
-				__LINE__, err, __rdpkru(), shadow_pkru);
-		rdpkru(); /* for shadow checking */
-		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
+		dprintf4("%s()::%d, err: %d pkey_reg: 0x%x shadow: 0x%x\n",
+			__func__, __LINE__, err, __rdpkey_reg(),
+			shadow_pkey_reg);
+		rdpkey_reg(); /* for shadow checking */
+		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno,
+			ENOSPC);
 		if ((new_pkey == -1) && (errno == ENOSPC)) {
-			dprintf2("%s() failed to allocate pkey after %d tries\n",
+			dprintf2("%s() allocate failed pkey after %d tries\n",
 				__func__, nr_allocated_pkeys);
 			break;
 		}
@@ -1165,19 +1255,17 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
 	 * failure:
 	 */
 	pkey_assert(i < NR_PKEYS*2);
-
 	/*
-	 * There are 16 pkeys supported in hardware.  One is taken
-	 * up for the default (0) and another can be taken up by
-	 * an execute-only mapping.  Ensure that we can allocate
-	 * at least 14 (16-2).
+	 * There are NR_PKEYS pkeys supported in hardware.  NR_RESERVED_KEYS
+	 * are reserved. One can be taken up by an execute-only mapping.
+	 * Ensure that we can allocate at least the remaining.
 	 */
-	pkey_assert(i >= NR_PKEYS-2);
+	pkey_assert(i >= (NR_PKEYS-NR_RESERVED_PKEYS-1));
 
 	for (i = 0; i < nr_allocated_pkeys; i++) {
 		err = sys_pkey_free(allocated_pkeys[i]);
 		pkey_assert(!err);
-		rdpkru(); /* for shadow checking */
+		rdpkey_reg(); /* for shadow checking */
 	}
 }
 
@@ -1221,10 +1309,10 @@ void test_ptrace_of_child(int *ptr, u16 pkey)
 	pkey_write_deny(pkey);
 
 	/* Write access, untested for now:
-	ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
-	pkey_assert(ret != -1);
-	dprintf1("poke at %p: %ld\n", peek_at, ret);
-	*/
+	 * ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
+	 * pkey_assert(ret != -1);
+	 * dprintf1("poke at %p: %ld\n", peek_at, ret);
+	 */
 
 	/*
 	 * Try to access the pkey-protected "ptr" via ptrace:
@@ -1234,7 +1322,7 @@ void test_ptrace_of_child(int *ptr, u16 pkey)
 	pkey_assert(ret != -1);
 	/* Now access from the current task, and expect an exception: */
 	peek_result = read_ptr(ptr);
-	expected_pk_fault(pkey);
+	expected_pkey_faults(pkey);
 
 	/*
 	 * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
@@ -1281,7 +1369,7 @@ void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
 	pkey_assert(!ret);
 	pkey_access_deny(pkey);
 
-	dprintf2("pkru: %x\n", rdpkru());
+	dprintf2("pkey_reg: %x\n", rdpkey_reg());
 
 	/*
 	 * Make sure this is an *instruction* fault
@@ -1291,7 +1379,7 @@ void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
 	do_not_expect_pk_fault();
 	ptr_contents = read_ptr(p1);
 	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
-	expected_pk_fault(pkey);
+	expected_pkey_faults(pkey);
 }
 
 void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
@@ -1299,7 +1387,7 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
 	int size = PAGE_SIZE;
 	int sret;
 
-	if (cpu_has_pku()) {
+	if (cpu_has_pkey()) {
 		dprintf1("SKIP: %s: no CPU support\n", __func__);
 		return;
 	}
@@ -1311,8 +1399,11 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
 void (*pkey_tests[])(int *ptr, u16 pkey) = {
 	test_read_of_write_disabled_region,
 	test_read_of_access_disabled_region,
+	test_read_of_access_disabled_region_with_page_already_mapped,
 	test_write_of_write_disabled_region,
+	test_write_of_write_disabled_region_with_page_already_mapped,
 	test_write_of_access_disabled_region,
+	test_write_of_access_disabled_region_with_page_already_mapped,
 	test_kernel_write_of_access_disabled_region,
 	test_kernel_write_of_write_disabled_region,
 	test_kernel_gup_of_access_disabled_region,
@@ -1331,7 +1422,7 @@ void run_tests_once(void)
 
 	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
 		int pkey;
-		int orig_pkru_faults = pkru_faults;
+		int orig_pkey_faults = pkey_faults;
 
 		dprintf1("======================\n");
 		dprintf1("test %d preparing...\n", test_nr);
@@ -1346,45 +1437,42 @@ void run_tests_once(void)
 		free_pkey_malloc(ptr);
 		sys_pkey_free(pkey);
 
-		dprintf1("pkru_faults: %d\n", pkru_faults);
-		dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
+		dprintf1("pkey_faults: %d\n", pkey_faults);
+		dprintf1("orig_pkey_faults: %d\n", orig_pkey_faults);
 
 		tracing_off();
 		close_test_fds();
 
-		printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
+		printf("test %2d PASSED (iteration %d)\n",
+				test_nr, iteration_nr);
 		dprintf1("======================\n\n");
 	}
 	iteration_nr++;
 }
 
-void pkey_setup_shadow(void)
-{
-	shadow_pkru = __rdpkru();
-}
-
 int main(void)
 {
 	int nr_iterations = 22;
 
 	setup_handlers();
 
-	printf("has pku: %d\n", cpu_has_pku());
+	printf("has pkey support: %d\n", cpu_has_pkey());
 
-	if (!cpu_has_pku()) {
+	if (!cpu_has_pkey()) {
 		int size = PAGE_SIZE;
 		int *ptr;
 
 		printf("running PKEY tests for unsupported CPU/OS\n");
 
-		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+		ptr  = mmap(NULL, size, PROT_NONE,
+				MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 		assert(ptr != (void *)-1);
 		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
 		exit(0);
 	}
 
 	pkey_setup_shadow();
-	printf("startup pkru: %x\n", rdpkru());
+	printf("startup pkey_reg: %lx\n", rdpkey_reg());
 	setup_hugetlbfs();
 
 	while (nr_iterations-- > 0)
-- 
1.8.3.1

[RFC v3 21/23] Documentation: Move protecton key documentation to arch neutral directory

[Ram Pai]

Since PowerPC and Intel both support memory protection keys, moving
the documenation to arch-neutral directory.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 Documentation/vm/protection-keys.txt  | 85 +++++++++++++++++++++++++++++++++++
 Documentation/x86/protection-keys.txt | 85 -----------------------------------
 2 files changed, 85 insertions(+), 85 deletions(-)
 create mode 100644 Documentation/vm/protection-keys.txt
 delete mode 100644 Documentation/x86/protection-keys.txt

diff --git a/Documentation/vm/protection-keys.txt b/Documentation/vm/protection-keys.txt
new file mode 100644
index 0000000..b643045
--- /dev/null
+++ b/Documentation/vm/protection-keys.txt
@@ -0,0 +1,85 @@
+Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
+which will be found on future Intel CPUs.
+
+Memory Protection Keys provides a mechanism for enforcing page-based
+protections, but without requiring modification of the page tables
+when an application changes protection domains.  It works by
+dedicating 4 previously ignored bits in each page table entry to a
+"protection key", giving 16 possible keys.
+
+There is also a new user-accessible register (PKRU) with two separate
+bits (Access Disable and Write Disable) for each key.  Being a CPU
+register, PKRU is inherently thread-local, potentially giving each
+thread a different set of protections from every other thread.
+
+There are two new instructions (RDPKRU/WRPKRU) for reading and writing
+to the new register.  The feature is only available in 64-bit mode,
+even though there is theoretically space in the PAE PTEs.  These
+permissions are enforced on data access only and have no effect on
+instruction fetches.
+
+=========================== Syscalls ===========================
+
+There are 3 system calls which directly interact with pkeys:
+
+	int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
+	int pkey_free(int pkey);
+	int pkey_mprotect(unsigned long start, size_t len,
+			  unsigned long prot, int pkey);
+
+Before a pkey can be used, it must first be allocated with
+pkey_alloc().  An application calls the WRPKRU instruction
+directly in order to change access permissions to memory covered
+with a key.  In this example WRPKRU is wrapped by a C function
+called pkey_set().
+
+	int real_prot = PROT_READ|PROT_WRITE;
+	pkey = pkey_alloc(0, PKEY_DENY_WRITE);
+	ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+	ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
+	... application runs here
+
+Now, if the application needs to update the data at 'ptr', it can
+gain access, do the update, then remove its write access:
+
+	pkey_set(pkey, 0); // clear PKEY_DENY_WRITE
+	*ptr = foo; // assign something
+	pkey_set(pkey, PKEY_DENY_WRITE); // set PKEY_DENY_WRITE again
+
+Now when it frees the memory, it will also free the pkey since it
+is no longer in use:
+
+	munmap(ptr, PAGE_SIZE);
+	pkey_free(pkey);
+
+(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
+ An example implementation can be found in
+ tools/testing/selftests/x86/protection_keys.c)
+
+=========================== Behavior ===========================
+
+The kernel attempts to make protection keys consistent with the
+behavior of a plain mprotect().  For instance if you do this:
+
+	mprotect(ptr, size, PROT_NONE);
+	something(ptr);
+
+you can expect the same effects with protection keys when doing this:
+
+	pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ);
+	pkey_mprotect(ptr, size, PROT_READ|PROT_WRITE, pkey);
+	something(ptr);
+
+That should be true whether something() is a direct access to 'ptr'
+like:
+
+	*ptr = foo;
+
+or when the kernel does the access on the application's behalf like
+with a read():
+
+	read(fd, ptr, 1);
+
+The kernel will send a SIGSEGV in both cases, but si_code will be set
+to SEGV_PKERR when violating protection keys versus SEGV_ACCERR when
+the plain mprotect() permissions are violated.
diff --git a/Documentation/x86/protection-keys.txt b/Documentation/x86/protection-keys.txt
deleted file mode 100644
index b643045..0000000
--- a/Documentation/x86/protection-keys.txt
+++ /dev/null
@@ -1,85 +0,0 @@
-Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
-which will be found on future Intel CPUs.
-
-Memory Protection Keys provides a mechanism for enforcing page-based
-protections, but without requiring modification of the page tables
-when an application changes protection domains.  It works by
-dedicating 4 previously ignored bits in each page table entry to a
-"protection key", giving 16 possible keys.
-
-There is also a new user-accessible register (PKRU) with two separate
-bits (Access Disable and Write Disable) for each key.  Being a CPU
-register, PKRU is inherently thread-local, potentially giving each
-thread a different set of protections from every other thread.
-
-There are two new instructions (RDPKRU/WRPKRU) for reading and writing
-to the new register.  The feature is only available in 64-bit mode,
-even though there is theoretically space in the PAE PTEs.  These
-permissions are enforced on data access only and have no effect on
-instruction fetches.
-
-=========================== Syscalls ===========================
-
-There are 3 system calls which directly interact with pkeys:
-
-	int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
-	int pkey_free(int pkey);
-	int pkey_mprotect(unsigned long start, size_t len,
-			  unsigned long prot, int pkey);
-
-Before a pkey can be used, it must first be allocated with
-pkey_alloc().  An application calls the WRPKRU instruction
-directly in order to change access permissions to memory covered
-with a key.  In this example WRPKRU is wrapped by a C function
-called pkey_set().
-
-	int real_prot = PROT_READ|PROT_WRITE;
-	pkey = pkey_alloc(0, PKEY_DENY_WRITE);
-	ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
-	... application runs here
-
-Now, if the application needs to update the data at 'ptr', it can
-gain access, do the update, then remove its write access:
-
-	pkey_set(pkey, 0); // clear PKEY_DENY_WRITE
-	*ptr = foo; // assign something
-	pkey_set(pkey, PKEY_DENY_WRITE); // set PKEY_DENY_WRITE again
-
-Now when it frees the memory, it will also free the pkey since it
-is no longer in use:
-
-	munmap(ptr, PAGE_SIZE);
-	pkey_free(pkey);
-
-(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
- An example implementation can be found in
- tools/testing/selftests/x86/protection_keys.c)
-
-=========================== Behavior ===========================
-
-The kernel attempts to make protection keys consistent with the
-behavior of a plain mprotect().  For instance if you do this:
-
-	mprotect(ptr, size, PROT_NONE);
-	something(ptr);
-
-you can expect the same effects with protection keys when doing this:
-
-	pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ);
-	pkey_mprotect(ptr, size, PROT_READ|PROT_WRITE, pkey);
-	something(ptr);
-
-That should be true whether something() is a direct access to 'ptr'
-like:
-
-	*ptr = foo;
-
-or when the kernel does the access on the application's behalf like
-with a read():
-
-	read(fd, ptr, 1);
-
-The kernel will send a SIGSEGV in both cases, but si_code will be set
-to SEGV_PKERR when violating protection keys versus SEGV_ACCERR when
-the plain mprotect() permissions are violated.
-- 
1.8.3.1

[RFC v3 22/23] Documentation: PowerPC specific updates to memory protection keys

[Ram Pai]

Add documentation updates that capture PowerPC specific changes.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 Documentation/vm/protection-keys.txt | 65 +++++++++++++++++++++++++-----------
 1 file changed, 45 insertions(+), 20 deletions(-)

diff --git a/Documentation/vm/protection-keys.txt b/Documentation/vm/protection-keys.txt
index b643045..965ad75 100644
--- a/Documentation/vm/protection-keys.txt
+++ b/Documentation/vm/protection-keys.txt
@@ -1,21 +1,46 @@
-Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
-which will be found on future Intel CPUs.
+Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature found in
+new generation of intel CPUs and on PowerPC 7 and higher CPUs.
 
 Memory Protection Keys provides a mechanism for enforcing page-based
-protections, but without requiring modification of the page tables
-when an application changes protection domains.  It works by
-dedicating 4 previously ignored bits in each page table entry to a
-"protection key", giving 16 possible keys.
-
-There is also a new user-accessible register (PKRU) with two separate
-bits (Access Disable and Write Disable) for each key.  Being a CPU
-register, PKRU is inherently thread-local, potentially giving each
-thread a different set of protections from every other thread.
-
-There are two new instructions (RDPKRU/WRPKRU) for reading and writing
-to the new register.  The feature is only available in 64-bit mode,
-even though there is theoretically space in the PAE PTEs.  These
-permissions are enforced on data access only and have no effect on
+protections, but without requiring modification of the page tables when an
+application changes protection domains.
+
+
+On Intel:
+
+	It works by dedicating 4 previously ignored bits in each page table
+	entry to a "protection key", giving 16 possible keys.
+
+	There is also a new user-accessible register (PKRU) with two separate
+	bits (Access Disable and Write Disable) for each key.  Being a CPU
+	register, PKRU is inherently thread-local, potentially giving each
+	thread a different set of protections from every other thread.
+
+	There are two new instructions (RDPKRU/WRPKRU) for reading and writing
+	to the new register.  The feature is only available in 64-bit mode,
+	even though there is theoretically space in the PAE PTEs.  These
+	permissions are enforced on data access only and have no effect on
+	instruction fetches.
+
+
+On PowerPC:
+
+	It works by dedicating 5 page table entry bits to a "protection key",
+	giving 32 possible keys.
+
+	There  is  a  user-accessible  register (AMR)  with  two separate bits;
+	Access Disable and  Write  Disable, for  each key.  Being  a  CPU
+	register,  AMR  is inherently  thread-local,  potentially  giving  each
+	thread a different set of protections from every other thread.  NOTE:
+	Disabling read permission does not disable write and vice-versa.
+
+	The feature is available on 64-bit HPTE mode only.
+	'mtspr 0xd, mem' reads the AMR register
+	'mfspr mem, 0xd' writes into the AMR register.
+
+
+
+Permissions are enforced on data access only and have no effect on
 instruction fetches.
 
 =========================== Syscalls ===========================
@@ -28,9 +53,9 @@ There are 3 system calls which directly interact with pkeys:
 			  unsigned long prot, int pkey);
 
 Before a pkey can be used, it must first be allocated with
-pkey_alloc().  An application calls the WRPKRU instruction
+pkey_alloc().  An application calls the WRPKRU/AMR instruction
 directly in order to change access permissions to memory covered
-with a key.  In this example WRPKRU is wrapped by a C function
+with a key.  In this example WRPKRU/AMR is wrapped by a C function
 called pkey_set().
 
 	int real_prot = PROT_READ|PROT_WRITE;
@@ -52,11 +77,11 @@ is no longer in use:
 	munmap(ptr, PAGE_SIZE);
 	pkey_free(pkey);
 
-(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
+(Note: pkey_set() is a wrapper for the RDPKRU,WRPKRU or AMR instructions.
  An example implementation can be found in
  tools/testing/selftests/x86/protection_keys.c)
 
-=========================== Behavior ===========================
+=========================== Behavior =================================
 
 The kernel attempts to make protection keys consistent with the
 behavior of a plain mprotect().  For instance if you do this:
-- 
1.8.3.1

[RFC v3 23/23] procfs: display the protection-key number associated with a vma

[Ram Pai]

Display the pkey number associated with the vma in smaps of a task.
The key will be seen as below:

VmFlags: rd wr mr mw me dw ac key=0

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
---
 Documentation/filesystems/proc.txt |  3 ++-
 fs/proc/task_mmu.c                 | 22 +++++++++++-----------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 4cddbce..a8c74aa 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -423,7 +423,7 @@ SwapPss:               0 kB
 KernelPageSize:        4 kB
 MMUPageSize:           4 kB
 Locked:                0 kB
-VmFlags: rd ex mr mw me dw
+VmFlags: rd ex mr mw me dw key=<num>
 
 the first of these lines shows the same information as is displayed for the
 mapping in /proc/PID/maps.  The remaining lines show the size of the mapping
@@ -491,6 +491,7 @@ manner. The codes are the following:
     hg  - huge page advise flag
     nh  - no-huge page advise flag
     mg  - mergable advise flag
+    key=<num> - the memory protection key number
 
 Note that there is no guarantee that every flag and associated mnemonic will
 be present in all further kernel releases. Things get changed, the flags may
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 2ddc298..d2eb096 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1,4 +1,6 @@
 #include <linux/mm.h>
+#include <linux/pkeys.h>
+#include <linux/huge_mm.h>
 #include <linux/vmacache.h>
 #include <linux/hugetlb.h>
 #include <linux/huge_mm.h>
@@ -666,22 +668,20 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_MERGEABLE)]	= "mg",
 		[ilog2(VM_UFFD_MISSING)]= "um",
 		[ilog2(VM_UFFD_WP)]	= "uw",
-#ifdef CONFIG_ARCH_HAS_PKEYS
-		/* These come out via ProtectionKey: */
-		[ilog2(VM_PKEY_BIT0)]	= "",
-		[ilog2(VM_PKEY_BIT1)]	= "",
-		[ilog2(VM_PKEY_BIT2)]	= "",
-		[ilog2(VM_PKEY_BIT3)]	= "",
-#endif /* CONFIG_ARCH_HAS_PKEYS */
-#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
-		/* Additional bit in ProtectionKey: */
-		[ilog2(VM_PKEY_BIT4)]	= "",
-#endif
 	};
 	size_t i;
 
 	seq_puts(m, "VmFlags: ");
 	for (i = 0; i < BITS_PER_LONG; i++) {
+#ifdef CONFIG_ARCH_HAS_PKEYS
+		if (i == ilog2(VM_PKEY_BIT0)) {
+			int keyvalue = vma_pkey(vma);
+
+			i += ilog2(arch_max_pkey())-1;
+			seq_printf(m, "key=%d ", keyvalue);
+			continue;
+		}
+#endif /* CONFIG_ARCH_HAS_PKEYS */
 		if (!mnemonics[i][0])
 			continue;
 		if (vma->vm_flags & (1UL << i)) {
-- 
1.8.3.1

Re: [RFC v3 01/23] powerpc: Free up four 64K PTE bits in 4K backed HPTE pages

[Balbir Singh]

On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> Rearrange 64K PTE bits to  free  up  bits 3, 4, 5  and  6,
> in the 4K backed HPTE pages. These bits continue to be used
> for 64K backed HPTE pages in this patch,  but will be freed
> up in the next patch. The  bit  numbers  are big-endian  as
> defined in the ISA3.0
> 
> The patch does the following change to the 64K PTE format
>

Why can't we stuff the bits in the VMA and retrieve it from there?
Basically always get a minor fault in hash and for keys handle
the fault in do_page_fault() and handle the keys from the VMA?
 
> H_PAGE_BUSY moves from bit 3 to bit 9
> H_PAGE_F_SECOND which occupied bit 4 moves to the second part
> 	of the pte.
> H_PAGE_F_GIX which  occupied bit 5, 6 and 7 also moves to the
> 	second part of the pte.
> 
> the four  bits((H_PAGE_F_SECOND|H_PAGE_F_GIX) that represent a slot
> is  initialized  to  0xF  indicating  an invalid  slot.  If  a HPTE
> gets cached in a 0xF  slot(i.e  7th  slot  of  secondary),  it   is
> released immediately. In  other  words, even  though   0xF   is   a
> valid slot we discard  and consider it as an invalid
> slot;i.e HPTE(). This  gives  us  an opportunity to not
> depend on a bit in the primary PTE in order to determine the
> validity of a slot.

This is not clear, could you please rephrase? What is the bit in the
primary key we rely on?

> 
> When  we  release  a    HPTE   in the 0xF   slot we also   release a
> legitimate primary   slot  and    unmap    that  entry. This  is  to
> ensure  that we do get a   legimate   non-0xF  slot the next time we
> retry for a slot.
> 
> Though treating 0xF slot as invalid reduces the number of available
> slots  and  may  have an effect  on the performance, the probabilty
> of hitting a 0xF is extermely low.
> 
> Compared  to the current scheme, the above described scheme reduces
> the number of false hash table updates  significantly  and  has the
> added  advantage  of  releasing  four  valuable  PTE bits for other
> purpose.
> 
> This idea was jointly developed by Paul Mackerras, Aneesh, Michael
> Ellermen and myself.
>

It would be helpful if you had a text diagram explaining the PTE bits
before and after.
 
> 4K PTE format remain unchanged currently.
>

The code seems to be doing a lot more than the changelog suggests. A few
functions are completely removed, common code between 64K and 4K has been
split under #ifndef. It would be good to call all of these out.
 
> Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> 
> Conflicts:
> 	arch/powerpc/include/asm/book3s/64/hash.h
> ---
>  arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++
>  arch/powerpc/include/asm/book3s/64/hash-64k.h | 17 ++++---
>  arch/powerpc/include/asm/book3s/64/hash.h     | 12 +++--
>  arch/powerpc/mm/hash64_64k.c                  | 70 +++++++++++++++------------
>  arch/powerpc/mm/hash_utils_64.c               |  4 +-
>  5 files changed, 66 insertions(+), 44 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> index b4b5e6b..9c2c8f1 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> @@ -16,6 +16,13 @@
>  #define H_PUD_TABLE_SIZE	(sizeof(pud_t) << H_PUD_INDEX_SIZE)
>  #define H_PGD_TABLE_SIZE	(sizeof(pgd_t) << H_PGD_INDEX_SIZE)
>  
> +#define H_PAGE_F_SECOND        _RPAGE_RSV2     /* HPTE is in 2ndary HPTEG */
> +#define H_PAGE_F_GIX           (_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> +#define H_PAGE_F_GIX_SHIFT     56
> +
> +#define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
> +#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
> +
>  /* PTE flags to conserve for HPTE identification */
>  #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | \
>  			 H_PAGE_F_SECOND | H_PAGE_F_GIX)
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> index 9732837..3f49941 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> @@ -10,20 +10,21 @@
>   * 64k aligned address free up few of the lower bits of RPN for us
>   * We steal that here. For more deatils look at pte_pfn/pfn_pte()
>   */
> -#define H_PAGE_COMBO	_RPAGE_RPN0 /* this is a combo 4k page */
> -#define H_PAGE_4K_PFN	_RPAGE_RPN1 /* PFN is for a single 4k page */
> +#define H_PAGE_COMBO   _RPAGE_RPN0 /* this is a combo 4k page */
> +#define H_PAGE_4K_PFN  _RPAGE_RPN1 /* PFN is for a single 4k page */

It would be good to split out these as cleanups, I can't see anything
change above, its a little confusing to review it.

> +#define H_PAGE_F_SECOND	_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
> +#define H_PAGE_F_GIX	(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> +#define H_PAGE_F_GIX_SHIFT	56
> +
> +#define H_PAGE_BUSY	_RPAGE_RPN42     /* software: PTE & hash are busy */
> +#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
> +
>  /*
>   * We need to differentiate between explicit huge page and THP huge
>   * page, since THP huge page also need to track real subpage details
>   */
>  #define H_PAGE_THP_HUGE  H_PAGE_4K_PFN
>  
> -/*
> - * Used to track subpage group valid if H_PAGE_COMBO is set
> - * This overloads H_PAGE_F_GIX and H_PAGE_F_SECOND
> - */
> -#define H_PAGE_COMBO_VALID	(H_PAGE_F_GIX | H_PAGE_F_SECOND)
> -
>  /* PTE flags to conserve for HPTE identification */
>  #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_F_SECOND | \
>  			 H_PAGE_F_GIX | H_PAGE_HASHPTE | H_PAGE_COMBO)
> diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
> index 4e957b0..ac049de 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash.h
> @@ -8,11 +8,8 @@
>   *
>   */
>  #define H_PTE_NONE_MASK		_PAGE_HPTEFLAGS
> -#define H_PAGE_F_GIX_SHIFT	56
> -#define H_PAGE_BUSY		_RPAGE_RSV1 /* software: PTE & hash are busy */
> -#define H_PAGE_F_SECOND		_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
> -#define H_PAGE_F_GIX		(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> -#define H_PAGE_HASHPTE		_RPAGE_RPN43	/* PTE has associated HPTE */
> +
> +#define INIT_HIDX (~0x0UL)
>  
>  #ifdef CONFIG_PPC_64K_PAGES
>  #include <asm/book3s/64/hash-64k.h>
> @@ -160,6 +157,11 @@ static inline int hash__pte_none(pte_t pte)
>  	return (pte_val(pte) & ~H_PTE_NONE_MASK) == 0;
>  }
>  
> +static inline bool hpte_soft_invalid(unsigned long slot)
> +{
> +	return ((slot & 0xfUL) == 0xfUL);
> +}
> +
>  /* This low level function performs the actual PTE insertion
>   * Setting the PTE depends on the MMU type and other factors. It's
>   * an horrible mess that I'm not going to try to clean up now but
> diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
> index 1a68cb1..a16cd28 100644
> --- a/arch/powerpc/mm/hash64_64k.c
> +++ b/arch/powerpc/mm/hash64_64k.c
> @@ -20,29 +20,7 @@
>   */
>  bool __rpte_sub_valid(real_pte_t rpte, unsigned long index)
>  {
> -	unsigned long g_idx;
> -	unsigned long ptev = pte_val(rpte.pte);
> -
> -	g_idx = (ptev & H_PAGE_COMBO_VALID) >> H_PAGE_F_GIX_SHIFT;
> -	index = index >> 2;
> -	if (g_idx & (0x1 << index))
> -		return true;
> -	else
> -		return false;
> -}
> -/*
> - * index from 0 - 15
> - */
> -static unsigned long mark_subptegroup_valid(unsigned long ptev, unsigned long index)
> -{
> -	unsigned long g_idx;
> -
> -	if (!(ptev & H_PAGE_COMBO))
> -		return ptev;
> -	index = index >> 2;
> -	g_idx = 0x1 << index;
> -
> -	return ptev | (g_idx << H_PAGE_F_GIX_SHIFT);
> +	return !(hpte_soft_invalid(rpte.hidx >> (index << 2)));
>  }
>  
>  int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> @@ -50,12 +28,11 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
>  		   int ssize, int subpg_prot)
>  {
>  	real_pte_t rpte;
> -	unsigned long *hidxp;
>  	unsigned long hpte_group;
>  	unsigned int subpg_index;
> -	unsigned long rflags, pa, hidx;
> +	unsigned long rflags, pa;
>  	unsigned long old_pte, new_pte, subpg_pte;
> -	unsigned long vpn, hash, slot;
> +	unsigned long vpn, hash, slot, gslot;
>  	unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift;
>  
>  	/*
> @@ -116,8 +93,8 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
>  		 * On hash insert failure we use old pte value and we don't
>  		 * want slot information there if we have a insert failure.
>  		 */
> -		old_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
> -		new_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
> +		old_pte &= ~(H_PAGE_HASHPTE);
> +		new_pte &= ~(H_PAGE_HASHPTE);
>  		goto htab_insert_hpte;
>  	}
>  	/*
> @@ -148,6 +125,15 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
>  	}
>  
>  htab_insert_hpte:
> +
> +	/*
> +	 * initialize all hidx entries to a invalid value,
> +	 * the first time the PTE is about to allocate
> +	 * a 4K hpte
> +	 */
> +	if (!(old_pte & H_PAGE_COMBO))
> +		rpte.hidx = INIT_HIDX;
> +
>  	/*
>  	 * handle H_PAGE_4K_PFN case
>  	 */
> @@ -172,15 +158,39 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
>  	 * Primary is full, try the secondary
>  	 */
>  	if (unlikely(slot == -1)) {
> +		bool soft_invalid;
> +
>  		hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
>  		slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
>  						rflags, HPTE_V_SECONDARY,
>  						MMU_PAGE_4K, MMU_PAGE_4K,
>  						ssize);
> -		if (slot == -1) {
> -			if (mftb() & 0x1)
> +
> +		soft_invalid = hpte_soft_invalid(slot);
> +		if (unlikely(soft_invalid)) {
> +			/* we got a valid slot from a hardware point of view.
> +			 * but we cannot use it, because we use this special
> +			 * value; as defined by hpte_soft_invalid(),
> +			 * to track invalid slots. We cannot use it.
> +			 * So invalidate it.
> +			 */

Comment style -- needs fixing

> +			gslot = slot & _PTEIDX_GROUP_IX;
> +			mmu_hash_ops.hpte_invalidate(hpte_group+gslot, vpn,
> +				MMU_PAGE_4K, MMU_PAGE_4K,
> +				ssize, 0);
> +		}
> +
> +		if (unlikely(slot == -1 || soft_invalid)) {
> +			/* for soft invalid slot lets ensure that we
> +			 * release a slot from the primary, with the
> +			 * hope that we will acquire that slot next
> +			 * time we try. This will ensure that we dont
> +			 * get the same soft-invalid slot.
> +			 */
> +			if (soft_invalid || (mftb() & 0x1))
>  				hpte_group = ((hash & htab_hash_mask) *
>  					      HPTES_PER_GROUP) & ~0x7UL;
> +
>  			mmu_hash_ops.hpte_remove(hpte_group);
>  			/*
>  			 * FIXME!! Should be try the group from which we removed ?
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index f2095ce..1b494d0 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -975,8 +975,9 @@ void __init hash__early_init_devtree(void)
>  
>  void __init hash__early_init_mmu(void)
>  {
> +#ifndef CONFIG_PPC_64K_PAGES
>  	/*
> -	 * We have code in __hash_page_64K() and elsewhere, which assumes it can
> +	 * We have code in __hash_page_4K() and elsewhere, which assumes it can
>  	 * do the following:
>  	 *   new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX);
>  	 *
> @@ -987,6 +988,7 @@ void __init hash__early_init_mmu(void)
>  	 * with a BUILD_BUG_ON().
>  	 */
>  	BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul  << (H_PAGE_F_GIX_SHIFT + 3)));
> +#endif /* CONFIG_PPC_64K_PAGES */
>  
>  	htab_init_page_sizes();
>

Balbir Singh.  

Re: [RFC v3 01/23] powerpc: Free up four 64K PTE bits in 4K backed HPTE pages

[Ram Pai]

On Thu, Jun 22, 2017 at 07:21:03PM +1000, Balbir Singh wrote:
> On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> > Rearrange 64K PTE bits to  free  up  bits 3, 4, 5  and  6,
> > in the 4K backed HPTE pages. These bits continue to be used
> > for 64K backed HPTE pages in this patch,  but will be freed
> > up in the next patch. The  bit  numbers  are big-endian  as
> > defined in the ISA3.0
> > 
> > The patch does the following change to the 64K PTE format
> >
> 
> Why can't we stuff the bits in the VMA and retrieve it from there?
> Basically always get a minor fault in hash and for keys handle
> the fault in do_page_fault() and handle the keys from the VMA?

I think you raise a valid point. We dont necessarily have to program
the pte. the hpte can be programmed directly from the key in the vma.
Just that the code becomes a little ugly to do so, since the
_hash_page_*() functions do not have access to the vma.

However we are also trying to maintain consistency between hpte and rpte
implementation. The keys have to be programmed into the rpte.
The patch is working towards enabling the consistency, so that
the same code can work on both, hpte for now and rpte in the future.

Maybe I can just do what you propose.  However this patch by itself
has value, because it frees up four valuable pte bits, irrespective
of whether we use it for memory keys. Let me see what others have
to say.  

Aneesh: thoughts?

> 
> > H_PAGE_BUSY moves from bit 3 to bit 9
> > H_PAGE_F_SECOND which occupied bit 4 moves to the second part
> > 	of the pte.
> > H_PAGE_F_GIX which  occupied bit 5, 6 and 7 also moves to the
> > 	second part of the pte.
> > 
> > the four  bits((H_PAGE_F_SECOND|H_PAGE_F_GIX) that represent a slot
> > is  initialized  to  0xF  indicating  an invalid  slot.  If  a HPTE
> > gets cached in a 0xF  slot(i.e  7th  slot  of  secondary),  it   is
> > released immediately. In  other  words, even  though   0xF   is   a
> > valid slot we discard  and consider it as an invalid
> > slot;i.e HPTE(). This  gives  us  an opportunity to not
> > depend on a bit in the primary PTE in order to determine the
> > validity of a slot.
> 
> This is not clear, could you please rephrase? What is the bit in the
> primary key we rely on?

(H_PAGE_F_SECOND|H_PAGE_F_GIX) bits, which is big-endian bits 3 4 5 and
6. They are currently used to track the validitiy of the 4k-hptes backing the
64k-pte.   Each bit tracks four 4k-hptes, for a total of sixteen
4k-hptes.


> 
> > 
> > When  we  release  a    HPTE   in the 0xF   slot we also   release a
> > legitimate primary   slot  and    unmap    that  entry. This  is  to
> > ensure  that we do get a   legimate   non-0xF  slot the next time we
> > retry for a slot.
> > 
> > Though treating 0xF slot as invalid reduces the number of available
> > slots  and  may  have an effect  on the performance, the probabilty
> > of hitting a 0xF is extermely low.
> > 
> > Compared  to the current scheme, the above described scheme reduces
> > the number of false hash table updates  significantly  and  has the
> > added  advantage  of  releasing  four  valuable  PTE bits for other
> > purpose.
> > 
> > This idea was jointly developed by Paul Mackerras, Aneesh, Michael
> > Ellermen and myself.
> >
> 
> It would be helpful if you had a text diagram explaining the PTE bits
> before and after.

ok. will add it in the next version.

> 
> > 4K PTE format remain unchanged currently.
> >
> 
> The code seems to be doing a lot more than the changelog suggests. A few
> functions are completely removed, common code between 64K and 4K has been
> split under #ifndef. It would be good to call all of these out.

ok. will do.

> 
> > Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> > 
> > Conflicts:
> > 	arch/powerpc/include/asm/book3s/64/hash.h
> > ---
> >  arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++
> >  arch/powerpc/include/asm/book3s/64/hash-64k.h | 17 ++++---
> >  arch/powerpc/include/asm/book3s/64/hash.h     | 12 +++--
> >  arch/powerpc/mm/hash64_64k.c                  | 70 +++++++++++++++------------
> >  arch/powerpc/mm/hash_utils_64.c               |  4 +-
> >  5 files changed, 66 insertions(+), 44 deletions(-)
> > 
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > index b4b5e6b..9c2c8f1 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > @@ -16,6 +16,13 @@
> >  #define H_PUD_TABLE_SIZE	(sizeof(pud_t) << H_PUD_INDEX_SIZE)
> >  #define H_PGD_TABLE_SIZE	(sizeof(pgd_t) << H_PGD_INDEX_SIZE)
> >  
> > +#define H_PAGE_F_SECOND        _RPAGE_RSV2     /* HPTE is in 2ndary HPTEG */
> > +#define H_PAGE_F_GIX           (_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> > +#define H_PAGE_F_GIX_SHIFT     56
> > +
> > +#define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
> > +#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
> > +
> >  /* PTE flags to conserve for HPTE identification */
> >  #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | \
> >  			 H_PAGE_F_SECOND | H_PAGE_F_GIX)
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > index 9732837..3f49941 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > @@ -10,20 +10,21 @@
> >   * 64k aligned address free up few of the lower bits of RPN for us
> >   * We steal that here. For more deatils look at pte_pfn/pfn_pte()
> >   */
> > -#define H_PAGE_COMBO	_RPAGE_RPN0 /* this is a combo 4k page */
> > -#define H_PAGE_4K_PFN	_RPAGE_RPN1 /* PFN is for a single 4k page */
> > +#define H_PAGE_COMBO   _RPAGE_RPN0 /* this is a combo 4k page */
> > +#define H_PAGE_4K_PFN  _RPAGE_RPN1 /* PFN is for a single 4k page */
> 
> It would be good to split out these as cleanups, I can't see anything
> change above, its a little confusing to review it.

Will have to split the patch further into smaller chunks. :-)   Will do.

> 
> > +#define H_PAGE_F_SECOND	_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
> > +#define H_PAGE_F_GIX	(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> > +#define H_PAGE_F_GIX_SHIFT	56
> > +
> > +#define H_PAGE_BUSY	_RPAGE_RPN42     /* software: PTE & hash are busy */
> > +#define H_PAGE_HASHPTE	_RPAGE_RPN43    /* PTE has associated HPTE */
> > +
> >  /*
> >   * We need to differentiate between explicit huge page and THP huge
> >   * page, since THP huge page also need to track real subpage details
> >   */
> >  #define H_PAGE_THP_HUGE  H_PAGE_4K_PFN
> >  
> > -/*
> > - * Used to track subpage group valid if H_PAGE_COMBO is set
> > - * This overloads H_PAGE_F_GIX and H_PAGE_F_SECOND
> > - */
> > -#define H_PAGE_COMBO_VALID	(H_PAGE_F_GIX | H_PAGE_F_SECOND)
> > -
> >  /* PTE flags to conserve for HPTE identification */
> >  #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_F_SECOND | \
> >  			 H_PAGE_F_GIX | H_PAGE_HASHPTE | H_PAGE_COMBO)
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
> > index 4e957b0..ac049de 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash.h
> > @@ -8,11 +8,8 @@
> >   *
> >   */
> >  #define H_PTE_NONE_MASK		_PAGE_HPTEFLAGS
> > -#define H_PAGE_F_GIX_SHIFT	56
> > -#define H_PAGE_BUSY		_RPAGE_RSV1 /* software: PTE & hash are busy */
> > -#define H_PAGE_F_SECOND		_RPAGE_RSV2	/* HPTE is in 2ndary HPTEG */
> > -#define H_PAGE_F_GIX		(_RPAGE_RSV3 | _RPAGE_RSV4 | _RPAGE_RPN44)
> > -#define H_PAGE_HASHPTE		_RPAGE_RPN43	/* PTE has associated HPTE */
> > +
> > +#define INIT_HIDX (~0x0UL)
> >  
> >  #ifdef CONFIG_PPC_64K_PAGES
> >  #include <asm/book3s/64/hash-64k.h>
> > @@ -160,6 +157,11 @@ static inline int hash__pte_none(pte_t pte)
> >  	return (pte_val(pte) & ~H_PTE_NONE_MASK) == 0;
> >  }
> >  
> > +static inline bool hpte_soft_invalid(unsigned long slot)
> > +{
> > +	return ((slot & 0xfUL) == 0xfUL);
> > +}
> > +
> >  /* This low level function performs the actual PTE insertion
> >   * Setting the PTE depends on the MMU type and other factors. It's
> >   * an horrible mess that I'm not going to try to clean up now but
> > diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
> > index 1a68cb1..a16cd28 100644
> > --- a/arch/powerpc/mm/hash64_64k.c
> > +++ b/arch/powerpc/mm/hash64_64k.c
> > @@ -20,29 +20,7 @@
> >   */
> >  bool __rpte_sub_valid(real_pte_t rpte, unsigned long index)
> >  {
> > -	unsigned long g_idx;
> > -	unsigned long ptev = pte_val(rpte.pte);
> > -
> > -	g_idx = (ptev & H_PAGE_COMBO_VALID) >> H_PAGE_F_GIX_SHIFT;
> > -	index = index >> 2;
> > -	if (g_idx & (0x1 << index))
> > -		return true;
> > -	else
> > -		return false;
> > -}
> > -/*
> > - * index from 0 - 15
> > - */
> > -static unsigned long mark_subptegroup_valid(unsigned long ptev, unsigned long index)
> > -{
> > -	unsigned long g_idx;
> > -
> > -	if (!(ptev & H_PAGE_COMBO))
> > -		return ptev;
> > -	index = index >> 2;
> > -	g_idx = 0x1 << index;
> > -
> > -	return ptev | (g_idx << H_PAGE_F_GIX_SHIFT);
> > +	return !(hpte_soft_invalid(rpte.hidx >> (index << 2)));
> >  }
> >  
> >  int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> > @@ -50,12 +28,11 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> >  		   int ssize, int subpg_prot)
> >  {
> >  	real_pte_t rpte;
> > -	unsigned long *hidxp;
> >  	unsigned long hpte_group;
> >  	unsigned int subpg_index;
> > -	unsigned long rflags, pa, hidx;
> > +	unsigned long rflags, pa;
> >  	unsigned long old_pte, new_pte, subpg_pte;
> > -	unsigned long vpn, hash, slot;
> > +	unsigned long vpn, hash, slot, gslot;
> >  	unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift;
> >  
> >  	/*
> > @@ -116,8 +93,8 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> >  		 * On hash insert failure we use old pte value and we don't
> >  		 * want slot information there if we have a insert failure.
> >  		 */
> > -		old_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
> > -		new_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
> > +		old_pte &= ~(H_PAGE_HASHPTE);
> > +		new_pte &= ~(H_PAGE_HASHPTE);
> >  		goto htab_insert_hpte;
> >  	}
> >  	/*
> > @@ -148,6 +125,15 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> >  	}
> >  
> >  htab_insert_hpte:
> > +
> > +	/*
> > +	 * initialize all hidx entries to a invalid value,
> > +	 * the first time the PTE is about to allocate
> > +	 * a 4K hpte
> > +	 */
> > +	if (!(old_pte & H_PAGE_COMBO))
> > +		rpte.hidx = INIT_HIDX;
> > +
> >  	/*
> >  	 * handle H_PAGE_4K_PFN case
> >  	 */
> > @@ -172,15 +158,39 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
> >  	 * Primary is full, try the secondary
> >  	 */
> >  	if (unlikely(slot == -1)) {
> > +		bool soft_invalid;
> > +
> >  		hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
> >  		slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
> >  						rflags, HPTE_V_SECONDARY,
> >  						MMU_PAGE_4K, MMU_PAGE_4K,
> >  						ssize);
> > -		if (slot == -1) {
> > -			if (mftb() & 0x1)
> > +
> > +		soft_invalid = hpte_soft_invalid(slot);
> > +		if (unlikely(soft_invalid)) {
> > +			/* we got a valid slot from a hardware point of view.
> > +			 * but we cannot use it, because we use this special
> > +			 * value; as defined by hpte_soft_invalid(),
> > +			 * to track invalid slots. We cannot use it.
> > +			 * So invalidate it.
> > +			 */
> 
> Comment style -- needs fixing
> 

hmm.. checkpatch.pl did not catch it.

> > +			gslot = slot & _PTEIDX_GROUP_IX;
> > +			mmu_hash_ops.hpte_invalidate(hpte_group+gslot, vpn,
> > +				MMU_PAGE_4K, MMU_PAGE_4K,
> > +				ssize, 0);
> > +		}
> > +
> > +		if (unlikely(slot == -1 || soft_invalid)) {
> > +			/* for soft invalid slot lets ensure that we
> > +			 * release a slot from the primary, with the
> > +			 * hope that we will acquire that slot next
> > +			 * time we try. This will ensure that we dont
> > +			 * get the same soft-invalid slot.
> > +			 */
> > +			if (soft_invalid || (mftb() & 0x1))
> >  				hpte_group = ((hash & htab_hash_mask) *
> >  					      HPTES_PER_GROUP) & ~0x7UL;
> > +
> >  			mmu_hash_ops.hpte_remove(hpte_group);
> >  			/*
> >  			 * FIXME!! Should be try the group from which we removed ?
> > diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> > index f2095ce..1b494d0 100644
> > --- a/arch/powerpc/mm/hash_utils_64.c
> > +++ b/arch/powerpc/mm/hash_utils_64.c
> > @@ -975,8 +975,9 @@ void __init hash__early_init_devtree(void)
> >  
> >  void __init hash__early_init_mmu(void)
> >  {
> > +#ifndef CONFIG_PPC_64K_PAGES
> >  	/*
> > -	 * We have code in __hash_page_64K() and elsewhere, which assumes it can
> > +	 * We have code in __hash_page_4K() and elsewhere, which assumes it can
> >  	 * do the following:
> >  	 *   new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX);
> >  	 *
> > @@ -987,6 +988,7 @@ void __init hash__early_init_mmu(void)
> >  	 * with a BUILD_BUG_ON().
> >  	 */
> >  	BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul  << (H_PAGE_F_GIX_SHIFT + 3)));
> > +#endif /* CONFIG_PPC_64K_PAGES */
> >  
> >  	htab_init_page_sizes();
> >
> 

Thanks for your comments,
RP

Re: [RFC v3 02/23] powerpc: introduce set_hidx_slot helper

[Balbir Singh]

On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> Introduce set_hidx_slot() which sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX)
> bits at  the  appropriate  location  in  the  PTE  of  4K  PTE.  In the
> case of 64K PTE, it sets the bits in the second part of the PTE. Though
> the implementation for the former just needs the slot parameter, it does
> take some additional parameters to keep the prototype consistent.
> 
> This function will come in handy as we  work  towards  re-arranging the
> bits in the later patches.
> 
> Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> ---
>  arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++++++
>  arch/powerpc/include/asm/book3s/64/hash-64k.h | 16 ++++++++++++++++
>  2 files changed, 23 insertions(+)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> index 9c2c8f1..cef644c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> @@ -55,6 +55,13 @@ static inline int hash__hugepd_ok(hugepd_t hpd)
>  }
>  #endif
>  
> +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> +			unsigned int subpg_index, unsigned long slot)
> +{
> +	return (slot << H_PAGE_F_GIX_SHIFT) &
> +		(H_PAGE_F_SECOND | H_PAGE_F_GIX);
> +}
> +

A comment on top would help explain that 4k and 64k are different, 64k
is a new layout.

>  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>  
>  static inline char *get_hpte_slot_array(pmd_t *pmdp)
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> index 3f49941..4bac70a 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> @@ -75,6 +75,22 @@ static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
>  	return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
>  }
>  
> +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> +		unsigned int subpg_index, unsigned long slot)
> +{
> +	unsigned long *hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
> +
> +	rpte.hidx &= ~(0xfUL << (subpg_index << 2));
> +	*hidxp = rpte.hidx  | (slot << (subpg_index << 2));
> +	/*
> +	 * Avoid race with __real_pte()
> +	 * hidx must be committed to memory before committing
> +	 * the pte.
> +	 */
> +	smp_wmb();

Whats the other paired barrier, is it in set_pte()?

> +	return 0x0UL;
> +}

We return 0 here and slot information for 4k pages, it is not that
clear

Balbir Singh.

Re: [RFC v3 02/23] powerpc: introduce set_hidx_slot helper

[Benjamin Herrenschmidt]

On Mon, 2017-06-26 at 09:03 +1000, Balbir Singh wrote:
> On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> > Introduce set_hidx_slot() which sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX)
> > bits at  the  appropriate  location  in  the  PTE  of  4K  PTE.  In the
> > case of 64K PTE, it sets the bits in the second part of the PTE. Though
> > the implementation for the former just needs the slot parameter, it does
> > take some additional parameters to keep the prototype consistent.
> > 
> > This function will come in handy as we  work  towards  re-arranging the
> > bits in the later patches.

The name somewhat sucks. Something like pte_set_hash_slot() or
something like that would be much more meaningful.

> > Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> > ---
> >  arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++++++
> >  arch/powerpc/include/asm/book3s/64/hash-64k.h | 16 ++++++++++++++++
> >  2 files changed, 23 insertions(+)
> > 
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > index 9c2c8f1..cef644c 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > @@ -55,6 +55,13 @@ static inline int hash__hugepd_ok(hugepd_t hpd)
> >  }
> >  #endif
> >  
> > +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> > +			unsigned int subpg_index, unsigned long slot)
> > +{
> > +	return (slot << H_PAGE_F_GIX_SHIFT) &
> > +		(H_PAGE_F_SECOND | H_PAGE_F_GIX);
> > +}
> > +
> 
> A comment on top would help explain that 4k and 64k are different, 64k
> is a new layout.
> 
> >  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> >  
> >  static inline char *get_hpte_slot_array(pmd_t *pmdp)
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > index 3f49941..4bac70a 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > @@ -75,6 +75,22 @@ static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
> >  	return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
> >  }
> >  
> > +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> > +		unsigned int subpg_index, unsigned long slot)
> > +{
> > +	unsigned long *hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
> > +
> > +	rpte.hidx &= ~(0xfUL << (subpg_index << 2));
> > +	*hidxp = rpte.hidx  | (slot << (subpg_index << 2));
> > +	/*
> > +	 * Avoid race with __real_pte()
> > +	 * hidx must be committed to memory before committing
> > +	 * the pte.
> > +	 */
> > +	smp_wmb();
> 
> Whats the other paired barrier, is it in set_pte()?
> 
> > +	return 0x0UL;
> > +}
> 
> We return 0 here and slot information for 4k pages, it is not that
> clear
> 
> Balbir Singh.

Re: [RFC v3 02/23] powerpc: introduce set_hidx_slot helper

[Ram Pai]

On Mon, Jun 26, 2017 at 09:03:18AM +1000, Balbir Singh wrote:
> On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> > Introduce set_hidx_slot() which sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX)
> > bits at  the  appropriate  location  in  the  PTE  of  4K  PTE.  In the
> > case of 64K PTE, it sets the bits in the second part of the PTE. Though
> > the implementation for the former just needs the slot parameter, it does
> > take some additional parameters to keep the prototype consistent.
> > 
> > This function will come in handy as we  work  towards  re-arranging the
> > bits in the later patches.
> > 
> > Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> > ---
> >  arch/powerpc/include/asm/book3s/64/hash-4k.h  |  7 +++++++
> >  arch/powerpc/include/asm/book3s/64/hash-64k.h | 16 ++++++++++++++++
> >  2 files changed, 23 insertions(+)
> > 
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > index 9c2c8f1..cef644c 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> > @@ -55,6 +55,13 @@ static inline int hash__hugepd_ok(hugepd_t hpd)
> >  }
> >  #endif
> >  
> > +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> > +			unsigned int subpg_index, unsigned long slot)
> > +{
> > +	return (slot << H_PAGE_F_GIX_SHIFT) &
> > +		(H_PAGE_F_SECOND | H_PAGE_F_GIX);
> > +}
> > +
> 
> A comment on top would help explain that 4k and 64k are different, 64k
> is a new layout.

ok.

> 
> >  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> >  
> >  static inline char *get_hpte_slot_array(pmd_t *pmdp)
> > diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > index 3f49941..4bac70a 100644
> > --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> > @@ -75,6 +75,22 @@ static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
> >  	return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
> >  }
> >  
> > +static inline unsigned long set_hidx_slot(pte_t *ptep, real_pte_t rpte,
> > +		unsigned int subpg_index, unsigned long slot)
> > +{
> > +	unsigned long *hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
> > +
> > +	rpte.hidx &= ~(0xfUL << (subpg_index << 2));
> > +	*hidxp = rpte.hidx  | (slot << (subpg_index << 2));
> > +	/*
> > +	 * Avoid race with __real_pte()
> > +	 * hidx must be committed to memory before committing
> > +	 * the pte.
> > +	 */
> > +	smp_wmb();
> 
> Whats the other paired barrier, is it in set_pte()?

 __real_pte() reads the hidx. The smp_rmb() is in that function.

> 
> > +	return 0x0UL;
> > +}
> 
> We return 0 here and slot information for 4k pages, it is not that
> clear

We return 0 here and commit the 4k-hpte hidx. 


RP

Re: [RFC v3 02/23] powerpc: introduce set_hidx_slot helper

[Ram Pai]

On Sun, Jun 25, 2017 at 11:02:58PM -0500, Benjamin Herrenschmidt wrote:
> On Mon, 2017-06-26 at 09:03 +1000, Balbir Singh wrote:
> > On Wed, 2017-06-21 at 18:39 -0700, Ram Pai wrote:
> > > Introduce set_hidx_slot() which sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX)
> > > bits at  the  appropriate  location  in  the  PTE  of  4K  PTE.  In the
> > > case of 64K PTE, it sets the bits in the second part of the PTE. Though
> > > the implementation for the former just needs the slot parameter, it does
> > > take some additional parameters to keep the prototype consistent.
> > > 
> > > This function will come in handy as we  work  towards  re-arranging the
> > > bits in the later patches.
> 
> The name somewhat sucks. Something like pte_set_hash_slot() or
> something like that would be much more meaningful.

ok. pte_set_hash_slot() sounds good.
RP